Jan. 17, 2006

Remember last week, when Cameron Diaz and Justin Timberlake announced they were kaput but continue to "love and respect" one another? Turns out the split might not be going quite as amicably as they'd hoped.

Video: Justin and Cameron call it quits

People reports Diaz, 34, and Timberlake, 25, ended up in a "heated argument" while partying at Prince's post-Golden Globes soiree in the early hours of Tuesday morning.

The night started off friendly enough for the former flames, who reportedly fizzled out last month after nearly four years of togetherness.

The mag says they chit-chatted during the ceremony and joked around at the In Style afterparty, but their tempers are said to have flared at the Beverly Wilshire hotel bash hosted by the diminutive pop icon.

And the spark that set them off may have been Jessica Biel.

Seems Justin's one-on-one time with the muscle-bound, callipygian beauty didn't sit well with his ex.

The New York Post claims that when Cameron spied them engaged in a tête-à-tête, she "blew up" and "screamed" at Jessica, who's recently been spending quality time with Derek Jeter.

"If that's how she wants to get him back, it won't work," a mole sniffs to the paper. "She's desperate."

But in People's version of events, Biel merely walked away when Diaz and her tragic ruffles of singledom approached.

The onetime lovebirds then proceeded to have a "serious exchange" before Cameron purportedly turned on her heel, prompting Justin to trail after her. A short time later, eyewitnesses clocked them having an "intense 40-minute face-off" in a privacy-challenged room.

A spy tells the mag that the "SexyBack" crooner held his head in his hands and "slammed" his fist down on a cabinet not long before the leggy actress reappeared "looking composed."

That's quite an emotional shift from their interactions earlier in the evening, when Timberlake moseyed over to Diaz at the In Style fete, where she was catching up with her "Gangs of New York" co-star Leonardo DiCaprio.

"When he first came in, Justin steered clear of her," an insider recounts to the New York Daily News. "But he made a beeline toward her when he saw her sitting on a couch with Leo DiCaprio."

Then, continues the bystander, "Justin smiled and raised his glass to Cameron and she did the same. Then he slid in next to her. They spent about 15 minutes talking, but didn't want anybody taking their picture."

And what of Timberlake's so-called "revenge romance" with Scarlett Johansson?

Us Weekly says the toothsome twosome, who warmed to each other while working on Timberlake's new video "What Goes Around," are keeping their fledgling coziness "casual," with the stacked starlet supposedly in a "single girl phase."

Says "a friend of the couple," "They're just having fun."