This is CNBC's live blog tracking developments on the war in Ukraine.  See here for the latest updates.

Ukraine recaptured two villages in the area around Bakhmut in Donetsk, eastern Ukraine, in recent days as its grueling counteroffensive continues in the south and east of the country.

Ukraine's Deputy Defense Minister Hanna Maliar said Monday that Kyiv's forces had liberated Andriivka and Klishchiivka over the weekend but said Russian was "trying with all his might to regain lost positions." 

Ukraine's President Volodymyr Zelenskyy congratulated his forces in the region in his nightly address Sunday, saying "I would like to especially recognize the warriors who are gradually regaining Ukraine's territory in the area of Bakhmut."

Ukraine's forces have also made modest gains in the south in the past week, regaining 2 square miles of territory in the area.

Ukraine plans lawsuit against Poland, Hungary and Slovakia over agricultural import restrictions

Ukraine intends to sue Poland, Hungary and Slovakia over their restrictions on Ukrainian agricultural imports, officials said.

Ukrainian Trade Representative Taras Kachka told Politico in an interview it was "important to prove that these actions are legally wrong," and that an appeal would be made through the World Trade Organization.

A senior Ukrainian official said an appeal could be sent "in the near future," Reuters reported Monday.

Poland, Hungary and Slovakia on Friday announced import curbs after European Commission-led restrictions on Ukrainian imports into the countries — as well as Romania and Bulgaria — expired. All five are EU members which are close to or border Ukraine.

The EU deal allowed products to transit via the countries but required them to be sold elsewhere. The three new national restrictions cover domestic imports and will still allow transit, Reuters reported.

Land exports from Ukraine have increased since the suspension of the Black Sea grain initiative by Russia in July, creating tensions with local farmers as goods prices fell.

Ukraine has agreed to introduce measures intended to prevent a "surge" in EU imports, however the details have not been specified.

Hungarian President Viktor Orban on Saturday wrote on social media website X that Ukrainian agricultural products destined for Africa were "flooding Central European markets."

A Polish government spokesperson said it was introducing the ban in the "interest of Polish farmers and consumers;" while Slovakia's Prime Minister Ľudovít Ódor said it would "prevent excessive pressure on the Slovak market in order to remain fair to our farmers as well."

— Jenni Reid

Four killed in Russian strikes, officials say

Four Ukrainian civilians were killed in Russian air strikes and shelling late Sunday and early Monday, officials reported.

A 72-year-old man and elderly woman were killed in southern Kherson, regional governor Oleksandr Prokudin said on the Telegram messaging app.

A man and woman were killed in separate incidents in the Donetsk region, Ukraine's general prosecutor's office said. CNBC has not independently verified the reports.

— Jenni Reid

Explosions reported at Russian administration building in occupied Donetsk

Explosions have been reported around the headquarters of the Russian authorities in Donetsk, news agency RIA Novosti said Monday.

The report said there was at least one hit on the building housing the authorities of the pro-Russian, so-called Donetsk People's Republic, or DPR. CNBC was unable to confirm the information reported by the Russian news agency.

Shortly after, RIA Novosti published an update in which a DPR representative claimed that Ukrainian forces had fired three missiles at the center of Donetsk. Ukraine has not commented on the incident which represents the latest effort to strike at the heart of Russian occupying forces in Ukraine.

Russia's invasion of Ukraine was preceded by Moscow's recognition of the breakaway regions of the DPR, and the neighboring Luhansk People's Republic, as independent states. Russia has supported and fomented pro-Russian separatism in both regions for years.

Russia has since tried to justify its invasion of Ukraine by saying it did so to protect the regions, which it has since incorporated into the Russian Federation following disputed referendums held last year on whether to join Russia. Russia said a majority of residents voted to join Russia but the votes were largely seen as coercive and bogus.

— Holly Ellyatt

Kremlin says it has no information on Chechen leader's health

The Kremlin says it has no information on the health of Chechen leader Ramzan Kadyrov following reports speculating that the ally of President Putin was unwell.

Several Ukrainian media reports, alongside unconfirmed information on various Telegram channels, recently speculated that Kadyrov was in a serious condition and had been treated in hospital, but two videos posted on Kadyrov's Telegram account on Sunday appeared to show him smiling and taking a walk. It's unknown when or where the videos were taken.

A comment accompanying the post said: "I strongly recommend that everyone who cannot distinguish the truth from lies on the internet go for a walk, get some fresh air and put their thoughts in order."

Asked about the state of Kadyrov's health, the Kremlin's Press Secretary Dmitry Peskov told reporters Monday that the Kremlin has "no information on this."

"In any case, the presidential administration can hardly give out health certificates, so we have nothing to tell you here," news agency RIA Novosti reported.

Reuters reported that spokespeople for Kadyrov did not answer repeated phone calls seeking comment on reports questioning his health.

Kadyrov has deployed Chechen forces to fight in Ukraine and has regularly spoken in support of Putin and Russia's invasion.

— Holly Ellyatt

Counteroffensive is 'not very fast' but is making progress, Zelenskyy says

Ukrainian President Volodymyr Zelenskyy acknowledged that the counteroffensive is not proceeding quickly but insisted Ukrainian forces are advancing and liberating Russian-occupied areas every day.

“It’s a difficult situation, I will be completely honest with you," Zelenskyy said in an interview with CBS News published on Sunday.

"We have the initiative. This is a plus. We stopped the Russian offensive and we moved onto a counter-offensive. And despite that, it’s not very fast. It is important that we are moving forward every day and liberating territory,” Zelenskyy added.

He noted that Ukraine needs to liberate its territory as much as possible. Time is of the essence in the south and east of Ukraine, where fighting is intense along a 900-mile long front line; Ukraine's infamous muddy season will return around October, making movement and progress more difficult.

“We need to liberate our territory as much as possible and move forward, even if it’s less than [half a mile or] a hundred [yards] we must do it. We mustn’t give Putin a break,” Zelenskyy noted.

— Holly Ellyatt

Russia calls on World Court to throw out Ukraine genocide case

Russia called on the U.N.'s highest court in The Hague on Monday to throw out a case that centres around claims by Moscow that its invasion of Ukraine was carried out to prevent genocide.

The request was made at the start of hearings dealing with the jurisdiction of the International Court of Justice (ICJ), also known as the World Court.

Ukraine brought the case just days after the Russian invasion on Feb. 24 last year. Kyiv argues Russia is abusing international law by saying the invasion was justified to prevent an alleged genocide in eastern Ukraine.

Russian officials continue to accuse Ukraine of committing genocide. On Monday, Russia repeated allegations that the "Russophobic and neo-Nazi regime in Kyiv" was using the 1948 Genocide Convention, to which both countries are a party, as a pretext to "drag" a case before the court.

Russia wants the case to be thrown out and says the court has no jurisdiction. The hearings, set to run until Sept. 27, will not delve into the merits of the case and are instead focused on legal arguments about jurisdiction.

"Ukraine is not accusing Russia of committing genocide. Ukraine is also not accusing Russia of failing to prevent or punish genocide. On the contrary, Ukraine insists no genocide has occurred," Russia's agent to the court, Gennady Kuzmin, said in opening remarks.

"That alone should be enough to reject the case. Because according to the court's jurisprudence, if there was no genocide, there cannot be a violation of the Genocide Convention."

While Russia has so far ignored the ICJ's orders to stop its military actions and the court has no way of enforcing its decisions, experts say an eventual ruling in favour of Ukraine could be important for any future reparations claims.

— Reuters

Russia is deploying elite airborne troops to bolster ground forces, UK says

Over the last two weeks, Russia has likely reinforced what Britain's Defense Ministry called its "hard-pressed" 58th Combined Arms Army in southern Ukraine with additional, elite airborne units.

"Throughout the war Russian commanders have attempted to regenerate the airborne forces as a highly mobile, striking force for offensive operations. Once again, they are being used as line infantry to augment over-stretched ground forces," the ministry said in an intelligence update Monday.

It noted that Russia appeared to be reinforcing its units in the area around the front-line town of Orikhiv in the Zaporizhzhia region of southern Ukraine, where Ukrainian forces are trying to advance and break through three main layers of Russian defenses.

The ministry said a total of at least five elite VDV [Russian airborne forces] regiments drawn from the 7th and 76th divisions, "are likely now concentrated within several kilometres of the frontline village of Robotyne."

"At full strength, such a force should constitute around 10,000 elite paratroopers. However, almost all units are highly likely dramatically under strength," the U.K. noted, adding that "the current situation is likely to be seen as highly unsatisfactory by the VDV hierarchy."

— Holly Ellyatt

China's Wang Yi visits Russia ahead of possible Xi-Putin meeting

China's top diplomat, Wang Yi, begins on Monday a four-day trip to Russia during which both nations are expected to pledge deeper mutual political trust, readying for a possible landmark visit by President Vladimir Putin to Beijing in October.

Wang, who heads the foreign ministry as well as the ruling Communist Party's foreign affairs office, will meet Security Council Secretary Nikolai Patrushev for annual security talks, the Chinese foreign ministry said in a statement.

The veteran diplomat's talks with counterpart Sergei Lavrov will cover a "wide range of issues" including "contacts at higher and the highest levels," the Russian foreign ministry said last week.

Wang is expected to lay the groundwork for Putin's visit to the Chinese capital for the third Belt and Road Forum after an invitation by President Xi Jinping during a high-profile visit to Moscow in March.

Putin attended China's first two Belt and Road Forums in 2017 and 2019. But he is not known to have travelled abroad since the International Criminal Court (ICC) issued an arrest warrant against him on grounds of illegally deporting hundreds of children from Ukraine.

On Sept. 1, Putin said he expected to meet Xi soon, but did not explicitly confirm that he would travel to China again.

The warrant, issued just days before Xi visited Russia, obligates the court's 123 member states to arrest Putin and transfer him to the Hague for trial if he enters their territory. However, China is not a party to the Rome Statute that led to the establishment of the ICC in 2002.

The visit will also see a detailed exchange of views on issues including Ukraine, ministry spokeswoman Maria Zakharova said last week.

— Reuters

Ukraine liberates two villages in the east as grueling counteroffensive continues

Ukraine recaptured two villages in the area around Bakhmut in Donetsk, eastern Ukraine, in recent days as its grueling counteroffensive continues in the south and east of the country.

Ukraine's Deputy Defense Minister Hanna Maliar said Monday that Kyiv's forces had liberated Andriivka and Klishchiivka over the weekend but said Russian was "trying with all his might to regain lost positions." 

"Our fighters hold back the enemy's attacks there and are entrenched at the achieved frontiers," she said in a post on Telegram. Two square kilometers, or 0.77 miles, of territory had been regained in the past week around Bakhmut, an epicenter of fighting for months.

Ukraine's President Volodymyr Zelenskyy congratulated his forces in the region in his nightly address Sunday, saying "I would like to especially recognize the warriors who are gradually regaining Ukraine's territory in the area of Bakhmut."

Ukrainian forces are also trying to push southward to regain towns and cities toward, and on, the Sea of Azov.

Maliar said Ukraine is continuing its "offensive operation in the Melitopol direction" and that there was success in the area south and east of Robotyne, a town in the southern Zaporizhia region that Ukraine said it had recaptured in late August.

In the past week, defense forces in the south have liberated 5.2 square km of territory. Since the start of the counteroffensive, 261.7 square km has been retaken in the region.

— Holly Ellyatt

Russians likely reinforcing Tokmak as Ukrainians push south

Russian troops have likely been reinforcing their defenses around the occupied town of Tokmak in southern Ukraine, Britain's Ministry of Defense said in an intelligence update Sunday.

"Tokmak is preparing to become a lynchpin of Russia's second main line of defences," the ministry said on X, formerly known as Twitter.

It noted that Russia is likely deploying additional checkpoints, "hedgehog" anti-tank defenses and digging new trenches in the area, which is held by its 58th Combined Arms Army. Tokmak is around 10 miles behind the current front line.

The ministry noted that improvements to the town's defenses likely indicate Russia's growing concern about Ukrainian tactical penetrations, in recent weeks, of the first main defensive line to the north.

— Holly Ellyatt