Cameron Diaz and Jessica Biel face off

It will take more than weedy Justin Timberlake to break up a catfight between Cameron Diaz and Jessica Biel if the two cross paths at the MTV Movie Awards on Sunday.

The situation between the two actresses is apparently serious enough for special arrangements to be made, with handlers of the girls reported to be working overtime to ensure they are kept away from each other to avoid any dramas.

Tense ... All eyes will be on Cameron Diaz (left) and her reaction to Jessica Biel (right)
and Justin Timberlake (inset) at the MTV Awards. [The Daily Telegraph]

The tension between the two leading ladies started at this year's Golden Globes, when Diaz had a huge fight with her then-recent ex, Justin Timberlake.

Diaz apparently spotted him flirting with Biel, his current girlfriend, at a Beverly Hills party.

This Sunday, the love triangle will reunite for the first time since that incident.

Sources told the NY Post that Diaz and Biel are both presenting awards at the ceremony, while Timberlake is nominated for best breakthrough performance for his role in "Alpha Dog."

"Everyone is determined to keep Cam and Jess far apart," said an insider. And Timberlake isn't helping by not revealing how he'll walk the carpet, solo or with Biel.

"It's becoming a big deal because the girls both want very separate arrival times," said the source.

"Nobody knows who Cameron is going to bring, if anyone. But if Jessica walks with Justin, Cameron will want to bring a date. If Jessica goes alone, Cam will probably walk alone. It's a mess."

"Cam is used to being more high-profile than Jessica," said the source. "But now that Jessica's dating Justin, she has more leverage. Cameron's looking a little unstable lately."

The ceremony is also being carefully crafted to avoid a run-in because Diaz was nominated in the best-kiss category (for her lip lock with Jude Law in "The Holiday").

"Jessica is definitely not presenting that one."