The duo lit up New York's Empire State Building together to celebrate the milestone.
Tony Bennett is celebrating his 90th birthday in style!
The iconic singer was joined by pal Lady Gaga to ring in the milestone on Wednesday, with the duo posing for photos as they lit up the Empire State Building in New York City. Gaga looked absolutely stunning in a long black gown with a strappy, criss-crossed back, pulling her platinum blonde hair back in a neat bun underneath a black brimmed hat. With her heart-shaped diamond engagement ring nowhere to be seen since splitting from Taylor Kinney last month, she accessorized on that finger with a chunky black bauble.
For his part, Bennett looked dapper in black slacks and a bright blue blazer, paired with a light blue shirt and yellow patterned tie.
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Becoming a nonogenarian doesn't seem to be slowing Bennett down! In addition to partying at the Rainbow Room at Radio City Music Hall for his birthday, he's also planning to begin work on a Cheek to Cheek follow-up with Gaga early next year.
"She's so busy right now, but at the beginning of next year we'll start doing an album," he told Billboard. "The first one went way over a million, and it's still selling."
The duo's collection of jazz duets debuted at No. 1 when it was released in September 2014, and the unlikely pair -- with nearly a 60 year age difference between them -- went on to score the GRAMMY award for Best Traditional Pop Vocal Album in 2015.
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Later this year, Bennett will publish a memoir, Just Getting Started, telling all on his famous friendships with the likes of Gaga, Amy Winehouse, Frank Sinatra, Judy Garland, Martin Luther King Jr., and more.
"The whole book is about different performers and just my experience about meeting them and the different things that happened and why they were so popular internationally throughout the world," Bennett told Billboard. "They're all people who were completely committed to doing great shows and great things, and they were all different, each of them. Each one is completely different than anyone else; They're just themselves."
Gaga has said she'll release a new solo album sometimes this year, while she's also returning to the small screen in the iteration of FX’s American Horror Story. Her role in AHS: Hotel scored the singer a Golden Globe award, but Bennett adorably told ET that he wasn't allowed to watch! See what he said in the video below.