Mayor de Blasio sang "I Love L.A." on "Jimmy Kimmel Live" Monday night to settle a Stanley Cup wager with Los Angeles Mayor Eric Garcetti.
De Blasio appeared via satellite from the ABC studios in Times Square as Garcetti joined the late-night host in his Los Angeles studio.
"Jimmy, I always wanted to meet you, but not like this man," said de Blasio, who was wearing a black T-shirt with the slogan "I (heart) LA."
"We New Yorkers honor our bets, but I don't have that great a singing voice," de Blasio said after Kimmel thanked the mayor for fulfilling the bet.
De Blasio then sang a verse and the chorus of "I love L.A." with 10 members from New York City's 52nd Street Project student chorus.
"Mayor de Blasio, you look like a counselor at the worst camp ever," Kimmel joked.
"Jimmy, this is a hostage situation," de Blasio retorted.
De Blasio also treated the studio audience in Los Angeles with Gray's Papaya hot dogs from New York, but Garcetti brought local favorites Pink's Hot Dogs.
"I'm going to stick with Pink's. They make those Gray's Papaya hot dogs taste like a steaming bag of New York garbage," Garcetti cracked.
Earlier in the day, Garcetti made waves when he let fly with the F-word in front of millions of people as he led his city in celebration of the Los Angeles Kings' second Stanley Cup championship in three years.
"There are two rules in politics," the usually soft-spoken mayor told the Kings and their fans. "They say never ever be pictured with a drink in your hand. And never ever swear.
"But this is a big f---ing day. Way to go, guys."
The Los Angeles Kings won the title on Friday night on home ice with a 3-2 victory over the New York Rangers.