Jen Lowery / Splash News 1 / 6
Jen Lowery / Splash News 1 / 6

Things could soon get really awkward on the set of "Gossip Girl." The romance between co-stars Ed Westwick and Jessica Szohr has supposedly ended in a fashion befitting the CW soap, complete with betrayal and a love triangle.

The New York Post says the British actor, 22, who has perfected the nostril-flaring sneer as Beau Brummel-loving Chuck Bass on the Upper East Side-set series, gave the dark-haired looker the heave-ho over the phone after he heard rumblings that she was "cozying up" to one of his pals while ringing in her 25th birthday.

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The third party in question is said to be Marco Minuto, a moneybags socialite with something of a colorful past.

"Jessica recently celebrated her birthday in L.A. and was being openly affectionate and flirty with Marco," alleges a source. "They ended up back at the same hotel, but nobody knows what happened behind closed doors. Her flirty behavior shocked a lot of their friends, so word quickly got back to Ed, who has been filming in Europe."

According to the snitch, Westwick "immediately ended their relationship on the phone, and Jessica, who denied anything happened with Marco, was so distraught that she flew to London last Friday with just the clothes on her back."

The starlet, who plays non-rich girl Vanessa on the show, has been "begging Ed to take her back, but he is deeply hurt," continues the insider. "He can't believe that she carried on this way with one of his friends."

Jessica's rep vehemently denies the two-timing accusations, scoffing to the paper that "the story has no merit," with a source adding that she's "been celebrating her birthday with Ed in London."

But a Westwick insider tells Gossip Cop that the duo is indeed kaput, insisting that Szohr's relationship-saving journey across the pond was for naught.

"Ed wanted no part of it. She cheated on him," claims the spy. "They're done."

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And this may not be the only "Gossip" breakup: OK! says Queen B Leighton Meester has handed boyfriend and occasional co-star Sebastian Stan his walking papers. But don't fret, Upper East Siders: At least we still have Serena and Dan Blake Lively and Penn Badgley.

Westwick and Szohr began dating more than a year ago after starting out as friends.

"It can be a little awkward when all of a sudden [you have feelings for] someone you'd call to talk about a different boyfriend," the actress explained during a recent interview with Teen Vogue. "But there wasn't a lot of thinking and talking. It kind of just happened. We had fun together, and we were like, 'All right, let's see where this goes.'"

And she enthused about Westwick's finer qualities.

"He's awesome and smart and talented and adorable, and we make each other laugh," she bubbled to the mag. "We go to dinners, have nights by ourselves and fun romantic times in general. And I like just cuddling up on the couch."

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