Blake Lively & Penn Badgley SPLIT: Breakup For 'Gossip Girl' Costars

Blake Lively and Penn Badgley have called it quits, their reps confirmed to Us Weekly.

The 'Gossip Girl' costars, both 23, began dating in 2007 and reportedly split in mid-September, keeping the news under wraps for the past few weeks.

"They're professionals," a source told Us Weekly. "They're still good friends and hang out on the set."

Blake spoke with Allure last month about wanting "lots of babies," but refused to comment on her relationship with Penn.

"Yeah, I don't comment on my relationships, so you can skip that one!" she said. "My anonymity is something I treasure. Wanting to be an actor and wanting to be famous are different."

Last weekend the former couple was snapped kissing on set, see pics at Celebuzz.

Us Weekly was the first to report the story, read more here.