Lindsay Lohan lparis.jpg Looks like Lindsay Lohan and Paris Hilton's mutually antagonistic relationship is back on last night, the two were spotted engaging in a vicious catfight at Timbaland's pre-Grammys party!

The Daily Mirror reports that, upon seeing her mortal frenemy arrive at the Avalon for the big bash, Lindsay snarled "What the hell is that bitch doing here? I didn't know she was on the list."

As you can imagine, Lindsay's outburst got a swift reaction from Paris - who retorted "F*ck off, you bitch!"

According to the Mirror, both Paris and Lindsay had come to Timbo's party to court the superproducer for their next albums. "Both saw the party as an ideal way of getting him on their side," a source close to the pair told the mag, "but they didn't count on the other being there."

The brouhaha started almost as soon as Paris showed up - and took a seat far closer to Tim than Lindsay's.

Lindsay responded by fluffing up her hair, taking a big swig of Red Bull, and scrambling over a sofa to make her way towards the super-producer - and to shoot Paris a withering glare, too.

Unfortunately for Linds, Paris was just a step quicker, as she leapt over a barrier and hurled herself at Timbaland.

The producer, however, was less than pleased at the sight - according to the mirror, he "gave both a blank stare before walking off."

Uh-oh - sounds like someone's going to have to Apologize to Timbo!