This was CNBC's live blog tracking developments on the war in Ukraine.

U.S. journalist Tucker Carlson has reportedly left Russia following his interview with Russian President Vladimir Putin, while Ukraine remains conspicuously silent on his request to interview Ukraine's leader Volodymyr Zelenskyy.

Russian online news outlet Mash published a photo of Carlson purportedly on a night flight from Moscow to Belgrade, Russian news agency Tass reported Thursday. CNBC was unable to verify the report.

The former Fox News host was spotted in Moscow earlier this week, fueling speculation that he was in Russia's capital to interview Putin. Carlson — who has expressed support for Russia — and the Kremlin confirmed that he had met and interviewed Putin Tuesday.

The interview will be broadcast later Thursday on X and Carlson's media startup at 18:00 ET.

Elsewhere, Zelenskyy announced a new top team for the Ukrainian Armed forces, fueling speculation that the conflict will take a new direction.

Zelenskyy appoints new army chief

President Volodymyr Zelenskyy announced a new top team for the Ukrainian Armed forces Thursday, writing in a post on Telegram.

General Oleksandr Syrskyi was named as the new commander-in-chief.

See the full post below translated by NBC News:

I am grateful to General Zaluzhnyy for two years of defense. I am thankful for every victory we have achieved together and thanks to all Ukrainian soldiers who heroically bear this war on themselves. We openly discussed today what changes are needed in the army. Urgent changes. I proposed to General Zaluzhny to continue together in the team of the Ukrainian state. I will be grateful for his consent.

Starting today, a new management team is taking over the leadership of the Armed Forces of Ukraine. I want the vision of the war to be unified among our soldiers in Robotyne or Avdiivka, as well as in the General Staff and at the Headquarters. I have had dozens of conversations with commanders of various levels. In particular, today I spoke with Brigadier Generals Andriy Hnatov, Mykhailo Drapaty, Ihor Skybiuk, and Colonels Pavlo Palysia and Vadym Sukharevskyy. They are all considered for leadership positions in the army and will serve under the leadership of the most experienced Ukrainian commander. He has successful experience in defense - he led the Kyiv Defense Operation. He also has successful experience in offense - the Kharkiv Liberation Operation. I have appointed Lieutenant General Syrskyy as the Commander-in-Chief of the Armed Forces of Ukraine.

Today, I also spoke with Generals Moisyuk and Zabrodskyy. Their experience is in service to the state.

2024 can be successful for Ukraine only if effective changes are made in the foundation of our defense, which is the Armed Forces of Ukraine

-Matt Clinch

Zelenskyy says changes in the military are needed

Ukraine's leader Volodymyr Zelenskyy took to X Thursday to say he had asked his Army Commander-in-Chief Valerii Zaluzhnyi to stay as part of his leadership team.

He added that both had agreed that changes in the military were needed.

See the full post below translated by NBC News:

I met with General Valerii Zaluzhnyi.

I thanked him for the two years of defending Ukraine.

We discussed the renewal that the Armed Forces of Ukraine require.

We also discussed who could be part of the renewed leadership of the Armed Forces of Ukraine.

The time for such a renewal is now.

I proposed to General Zaluzhnyi to remain part of the team.

We will definitely win!

Glory to Ukraine!

-Matt Clinch

US Senate to vote on $95 billion Ukraine, Israel aid bill after failed border deal

The U.S. Senate was due to vote on Thursday on a $95.34 billion bill that includes aid for Ukraine, Israel and the Indo-Pacific, after Republicans blocked compromise legislation that also included a long-sought overhaul of immigration policy.

Democrats and Republicans spent hours discussing next steps on Wednesday after the broader effort failed, until Senate Democratic Majority Leader Chuck Schumer sent lawmakers home with plans to consider on Thursday a revised package that strips out the immigration provisions but leaves the foreign aid intact.

"We will be coming back tomorrow at noon and, hopefully, that will give the Republicans the time they need," Schumer said on Wednesday. "We will have this vote."

The security aid bill includes $61 billion for Ukraine as it battles a Russian invasion, $14 billion for Israel in its war against Hamas and $4.83 billion to support partners in the Indo-Pacific, including Taiwan, and deter
aggression by China.

Supporters of Ukraine have been struggling for much of the year to find a way to send more money to help Ukrainian President Volodymyr Zelenskiy's government. While lawmakers have approved more than $110 billion for Ukraine since the invasion began in February 2022, Congress has not passed any major aid
for Kyiv since Republicans took control of the House of Representatives in January 2023.

It's unclear whether the new bill would win the support of House Republicans.

— Reuters

Putin and Xi reject U.S. 'interference', praise their own ties and trade, Kremlin says

Russian President Vladimir Putin and Chinese President Xi Jinping spoke by phone on Thursday and both rejected what they called U.S. interference in the affairs of other countries, the Kremlin said.

Kremlin aide Yury Ushakov gave details of the call in a briefing to journalists, saying the two leaders had spoken of creating a "multipolar, fairer world order" in the face of U.S.-led efforts to contain both of Washington's biggest adversaries.

Putin and Xi would continue to have "close personal interaction" but there were no plans for reciprocal visits right now, Ushakov said.

China and Russia have grown closer and expanded trade ties in recent years as the United States and its allies imposed sanctions against both countries, particularly Moscow after its invasion of Ukraine in 2022.

Putin and Xi met twice last year as China-Russia trade hit $218.2 billion during January-November, according to Chinese customs data, achieving a goal set by the two countries in 2019 a year ahead of schedule.

Russia meanwhile leapfrogged Saudi Arabia to become China's top crude oil supplier in 2023, Chinese data showed last month.

The two countries would press on with joint energy projects in 2024, Ushakov said. Putin and Xi also discussed the situation in Ukraine and conflict resolution in the Middle East and see eye to eye on those conflicts, he said, without elaborating. Russia supported China's policy on Taiwan, he said.

— Reuters

'Overdrive': Kremlin comments on Tucker Carlson media frenzy

The Kremlin said the media frenzy around U.S. journalist Tucker Carlson's interview with Russian President Vladimir Putin this week had gone into "overdrive."

"The very personality of Carlson and his arrival in Russia and interview with Putin is an event that caused a particular reaction not only in America, but also in our country," Kremlin Press Secretary Dmitry Peskov told reporters Thursday.

"To be fair, the reaction sometimes ... went into an overdrive," he said, according to an NBC News translation.

Peskov acknowledged that Tucker Carlson's interview with Putin, due to be released Thursday at 6 p.m. ET, was "highly anticipated." Carlson's interview is the first to be conducted between a Western journalist and the president since Russia invaded Ukraine in early 2022. Russian state media tracked Carlson's movements around Moscow this week amid heightened speculation over his presence.

"Obviously, this is an interview that will be read and analyzed for days to come," Peskov said, adding that "any interview with the head of state is a very important event, especially an interview with a foreign representative. I don't think Carlson needs any of our protection. I think that he can stand up for himself," Peskov noted, appearing to refer to criticism of Carlson among Western media outlets.

Announcing the interview, Carlson claimed that "not a single Western journalist has bothered to interview the president" — a claim that even the Kremlin rejected, saying it had many requests for interviews — and that Western governments would try to censor his interview. 

Peskov said Russia's leadership had granted the interview in a bid to get Russia's perspective on global affairs to a mass audience.

"In addition to the not entirely sane voices in the United States, there are also sane voices there, so we'll see. It is important for us that as many people as possible across the world become familiar with the worldview and point of view of the head of the Russian state."

— Holly Ellyatt

Four candidates to run in Russian presidential election

Four candidates are set to stand in Russia's presidential election next month after the country's Central Election Commission barred several hopefuls from the vote.

Leonid Slutsky, the leader of Russia's Liberal Democratic Party (LDPR) will stand in the March 15-17 ballot, as well as Communist Party candidate Nikolai Kharitonov, and New People party candidate and Russian lawmaker Vladislav Davankov. They will be up against incumbent Vladimir Putin who is standing as an independent. Putin has been in power as prime minister or president since late 1999.

He's widely expected to win another six-year term in power given Russia's pro-Putin media coverage and the absence of non-systemic political opponents.

The Central Election Commission refused to register war critic Boris Nadezhdin (standing for the Civic Initiative party) and Communists of Russia Party Chairman Sergey Malinkovich while beauty blogger Rada Russkikh and environmental blogger Anatoly Batashev, both campaigning as independents, failed to collect the 300,000 signatures to support their respective bids.

"The grounds for refusal of registration are an insufficient number of reliable signatures and/or the identification of 5% or more of unreliable and invalid signatures of voters collected in support of the candidate's nomination," the CEC said on Telegram.

Commenting on the CEC's decisions, Kremlin Press Secretary Dmitry Peskov said that the commission had "clearly followed the rules established for candidates," news agency TASS reported.

— Holly Ellyatt

Capturing war-torn Avdiivka the 'primary focus' of Russian operations, UK notes

The war-ravaged town of Avdiivka in Donetsk, eastern Ukraine, remains a primary focus of Russian operations, Britain's Ministry of Defense said in an in intelligence update Thursday.

"Russia continues attacks in the south-eastern city limits, with urban street-to-street combat taking place. Over the past two weeks, Russian forces have likely rotated in additional forces to the Avdiivka sector, increasing the pressure on Ukrainian positions around the city," the ministry said on X.

Ukraine continues to conduct counterattacks to ensure the main supply route remains in use, the U.K. noted.

"Over the past four weeks, approximately 600 guided munitions have been launched against Ukrainian positions in Avdiivka from tactical aircraft," the U.K. noted.

"Russian sorties increased guided aerial munitions strikes from 30 to 50 per day on 5 February 2024, an increase of 66% over the last two weeks."

The ministry noted that Russian fighters are being forced to launch munitions at range, degrading their accuracy due to the continued threat of Ukrainian air defense.

"Russia is almost certain to continue offensive pressure in this area over the next several weeks, heavily leveraging tactical air power to support its effort."

— Holly Ellyatt

War critic Nadezhdin barred from running in election

Russia's electoral authorities have barred war critic Boris Nadezhdin from running in the presidential election next month, claiming that he had submitted too many "defective" signatures in support of his election bid.

Politicians who wish to run in Russian elections must submit at least 100,000 signatures (or more, in the case of independent candidates) in support of their candidacy.

Nadezhdin, a former Russian lawmaker and well-known political pundit in Russia, submitted 105,000 signatures last week to the Central Election Commission (CEC), which oversees elections in Russia.

The CEC said Thursday that Nadezhdin was not eligible to run because of the high percentage of defects in the voter signatures he collected in his support, Russian news agency Tass said. The CEC said more than 15% of the signatures were defective.

Nadezhdin's campaign group had said earlier this week that they would appeal the decision but CEC Chairwoman Ella Pamfilova said "the decision has been made,” Russian state news agency Tass reported.

The decision will come as no surprise to close watchers of Russian politics and Kremlin critics. Political analysts said it was extremely unlikely that an anti-war candidate, who has garnered a following among a metropolitan section of Russian voters, would be allowed to run in the election, with the Kremlin likely fearing a potential swell of support for Nadezhdin that it would have to suppress, as it has done with other political opponents.

Read more on the story here

— Holly Ellyatt

Ukraine says it downed 11 out of 17 Russia-launched drones

Ukrainian air defense and mobile drone hunter groups shot down 11 out of 17 Russia-launched drones over four regions of the country, the air force said on Thursday.

It said in a statement the Iranian-made Shahed drones were downed over the Odesa and Mykolayiv regions in the south, the Dnipropetrovsk region in the southeast, and the central Vinnytsia region.

Regional officials said the drone attack damaged more than 20 residential houses and commercial buildings in the city of Mykolayiv and hit civilian infrastructure facilities in Odesa on the Black Sea in the south. There were no casualties reported.

Details of damage in other regions were not immediately clear.

— Reuters

Ukraine conspicuously silent on Tucker Carlson interview request

Ukraine's leadership has remained conspicuously silent on U.S. journalist Tucker Carlson's interview request following the journalist's repeated criticism of Kyiv.

Carlson interviewed Russian President Vladimir Putin earlier this week. The former Fox News host has expressed pro-Kremlin views while disparaging U.S. support for Ukraine, criticizing Western media interviews with Ukraine's President Volodymyr Zelenskyy and the president himself, calling him "sweaty and rat-like" and a "persecutor of Christians."

Carlson said he'd also requested an interview with Ukraine's president, although there has been no public response from Kyiv. Zelenskyy has not commented on the Putin interview either.

Deputy Prime Minister Hanna Maliar noted on Telegram that "the only interview that is safe in this situation is an interrogation in The Hague," alluding to the arrest warrant issued by the International Criminal Court (ICC) for Putin, accusing him of the war crime of the illegal deportation of children from Ukraine. Russia said the ICC's actions were "outrageous" and that it did not recognize the jurisdiction of the ICC.

Russian state media tracked Tucker Carlson's every move while he was in Moscow, and Maliar noted that "the Russian information environment is happy that a famous American journalist will interview Putin."

"There are such democratic practices that can lead to the destruction of the bearers of democratic values," Maliar said.

"As soon as they start a discussion about why Putin is doing this; where something human is hidden in him, which will smile and make a witty joke; that freedom of speech must be absolute; that two sides must be listened to — the countdown to their influence in the world will begin. They will imperceptibly hand it over to Putin," she said.

"Putin's interview to anyone outside the Russian Federation is a recognition of his status and the opening of Pandora's box. A chain reaction follows," Maliar added.

— Holly Ellyatt

Tucker Carlson reportedly leaves Russia, faces criticism for interview

U.S. journalist Tucker Carlson has reportedly left Russia following his interview with Russian President Vladimir Putin. 

Russian online news outlet Mash published a photo of Carlson purportedly on a night flight from Moscow to Belgrade, Russian news agency Tass reported Thursday. CNBC was unable to verify the report.

The former Fox News host was spotted in Moscow earlier this week, fueling speculation that he was in Russia's capital to interview Putin.

Carlson — who has expressed support for Russia — and the Kremlin confirmed that he had met and interviewed Putin Tuesday. The interview will be broadcast later Thursday on X and Carlson's own website at 18:00 ET.

Announcing the interview on X, Carlson lambasted Western media outlets for their coverage of the war in Ukraine, claiming that "not a single Western journalist has bothered to interview the president," and that Western governments would try to censor his interview. He did not produce evidence to back up his claims.

Both Western and Russian journalists who have fled the country in order to be able to report on the war, without risking "disinformation" charges and possible imprisonment, hit back at Carlson's comments, saying interview requests were repeatedly refused by the Kremlin and that many journalists had been expelled from Russia or imprisoned for their work and the "freedom of speech" Carlson claims to champion.

— Holly Ellyatt

IAEA chief says nuclear power plant in Ukraine is 'relatively stable'

Following a visit to the Zaporizhzhia Nuclear Power Plant{=null} on Wednesday, Rafael Grossi, director general of the International Atomic Energy Agency, said it was "relatively stable."

"There have been less, episodes of direct attacks or shelling around it, which is a positive development, although we take it with enormous caution," he said. Grossi added that topics including water supply, which serves to cool the plant, and staffing by authorized personnel were also discussed on Wednesday.

The plant is located in Southern Ukraine and has been highly contested throughout the war, with both Russia and Ukraine accusing one another of endangering its safety.

— Sophie Kiderlin

Russian foreign ministry says air defense systems destroy several Ukrainian rockets

Russia's air defense systems on Wednesday destroyed seven rockets launched by Ukraine over the Belgorod region, the Russian foreign ministry said in a post on Telegram, according to a translation.

Two people were wounded and were being treated for their injuries, Vyacheslav Gladkov, the governor of Belgorod, said on Telegram, according to a translation. Various private houses and cars, as well as businesses, were damaged, he added.

In a separate Telegram post later in the day, the Russian foreign ministry said a further two Ukrainian unmanned aerial vehicles had been destroyed over the same Russian region.

CNBC was unable to independently verify the reports.

— Sophie Kiderlin

4 dead, 40 injured in Russian attack on Kyiv

Four people have died and a further 40 were injured in Russian missile attacks on Ukraine's capital Kyiv earlier Wednesday, Kyiv's city military administration said on Telegram.

Emergency services continue to work in the Holosiiv district of the capital, where several floors of an 18-story residential building were damaged as a result of a Russian missile attack, Kyiv's Mayor Vitaliy Klitschko said on Telegram. The four civilians who died in today's attack were residents of the building, he said.

Ukrainian air defense forces said earlier that 20 Russian missiles had been destroyed over Kyiv and on their approach to the city early Wednesday morning.

Describing the latest attack as "the third missile attack on Kyiv in 2024," the city's military administration said on Telegram that Russia had used a variety of cruise missiles to target the capital.

"The enemy used Kh-101/Kh-555/Kh-55 cruise missiles launched from Tu-95MS strategic bombers from the territory of the Russian Federation. The air raid alert in the capital lasted almost 3 hours. The missiles entered the capital in several waves from different directions," Serhiy Popko, the head of the Kyiv city military administration, noted.

— Holly Ellyatt

Kremlin confirms Tucker Carlson interview took place Tuesday

The Kremlin confirmed Wednesday that U.S. journalist Tucker Carlson conducted an interview with Russian President Vladimir Putin.

"Yes, I can confirm this," the Kremlin's Press Secretary Dmitry Peskov said Wednesday. "As soon as it [the interview] is prepared, it will be released," he told reporters, according to TASS news agency.

"He has a position that differs from the others. It is in no way pro-Russian, it is not pro-Ukrainian, it is rather pro-American," Peskov added.

"But at least it is contrastingly different from the position of traditional Anglo-Saxon media," he added.

The comments echo those made by Carlson in Moscow on Tuesday. Announcing his interview with Putin, Carlson said "we are not here because we love Vladimir Putin. We are here because we love the United States."

Carlson lambasted Western media as he laid out his reasons for interviewing Putin, saying they "lie" to their readers and do so "mostly by omission." Carlson also said he was defending freedom of speech. He also claimed that "not a single Western journalist has bothered to interview the president."

Peskov said Wednesday that "Mister Carlson is wrong" about the Kremlin not receiving interview requests from foreign media but said he couldn't be expected to know that.

The Kremlin receives "lot of requests for interviews with the president," Peskov said, "but, basically, when it comes to the countries of the collective West, we are talking about large online media, traditional television channels, large newspapers, which cannot boast of attempts to at least look impartial in terms of coverage. These are all media that take an exclusively one-sided position," he said.

"Of course, there is no desire to communicate with such media, and there is hardly any point in this, it is unlikely that there can be any benefit from this," he added.

Russia's media landscape is tightly-controlled by the Kremlin and is consistently careful to orchestrate favorable coverage (and to omit any criticism) of Russia's leadership. It's also rare for Western media outlets to be granted an audience with Putin and many foreign journalists have been expelled from Russia.

Aside from the repression of media freedoms, freedom of speech is frequently under attack in Russia and censorship has only increased since the war started almost two years ago; expressions of anti-war sentiment can lead to arrest in Russia, with legislation making any perceived "disinformation" about Russia's armed forces a criminal offence.

— Holly Ellyatt

Read CNBC's previous live coverage here:

Tucker Carlson teases interview with Putin; Kremlin says ex-Fox News host is not ‘pro-Russian’