Avril Lavigne has resolved her differences with pop rival Britney and recruited her as her new party pal. Their new friendship comes just four months after Lavigne, 22, criticised Spears for being too weak to handle the pressures of fame.

Referring to the fallen pop superstar's brief stint in rehab, she said:

"What's happened to Britney is all down to who she is as a person. If you want a piece of this business you have to be able to deal with it. You can't complain about the pressures, the paparazzi, the madness, because that's your job."

Lavigne has also previously hit out at the 25-year-old mother-of-two for dressing "like a showgirl". (gasp)

But in true Hollywood fashion, the pop pair have decided that if you can't beat em, join em, and have now managed to put their problems behind them. Hours after Spears was ordered to submit to random drug and alcohol tests as part of her ongoing child custody battle, the singer was out on the town in Hollywood.

Spears joined pals at club Hyde late on Tuesday night, where she met Lavigne and shared a ride to another hotspot, Winston's.

Swarmed by paparazzi, Spears later pulled into the Beverly Hills Police Station and asked officers for an escort home. Poor poppet.