Yup, it's on!

Katy Perry and John Mayer were photographed together for the first time in L.A. on Wednesday night. Perry, 27, and Mayer, 34, had a leisurely dinner together at Chateau Marmont, an observer tells Us Weekly.

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And the date, the witness adds, was definitely romantic, with the "Teenage Dream" singer and Mayer "holding hands across the table," sneaking kisses, and laughing.

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Us Weekly was first to spot the newly divorced Perry and Mayer on a hot Friday night date June 19 at Soho House in West Hollywood. "They were affectionate, holding hands and cuddling!" an observer said of Perry and notorious ladies' man Mayer, whose exes include Jennifer Aniston, Jessica Simpson and Jennifer Love Hewitt. The couple met up the very next night at Perry's place, where they munched on pizza.

Perry, who recently finalized her divorce from Russell Brand, has had her eye on Mayer for a long time -- flirting up a storm with him way back in September 2009 at Golbar in NYC.

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"They're just hooking up right now," a source says. (Indeed, Perry has also been casually dating Florence and the Machine rocker Robert Ackroyd.) "It's not serious -- yet!"

This article originally appeared on Usmagazine.com: FIRST PIC: See Katy Perry, John Mayer Together on Sexy Date