Katy Perry taking Allison Williams to the Grammys

Katy Perry is leaving her boyfriend John Mayer at home on Sunday (10.02.13) and taking her good friend and 'Girls' star Allison Williams to the Grammy Awards instead.

Katy Perry is taking 'Girls' star Allison Williams to the Grammy Awards instead of her boyfriend John Mayer.

The 28-year-old singer - who is nominated in the Best Pop Solo Performance category for her 2012 hit 'Wide Awake' - will leave the 35-year-old musician at home on Sunday night (10.02.13) and attend the prestigious ceremony in Los Angeles with the brunette actress, who ''can't wait'' to go to the event.

Speaking on talk show 'Anderson Live', Allison - who plays Marine Michaels in the HBO drama series - said: ''I am going to the Grammys and Katy Perry is my date. She's the hottest date. She's a friend of mine and she's nominated as she should be. I can't wait to go. Obviously she's awesome. She's the best.''

Allison has become good friends with Katy - who is dating Ricky Van Veen, the founder of comedy website, CollegeHumor - after the pair met a few months ago through their boyfriends, and the two couples have been spotted together on double dates.

While John is being left at home by Katy on the weekend, he looks set to move in with her soon after he recently scheduled meetings with estate agents so the couple can get their own place together.

A source said: ''He always insisted he needed his own place to make music but clearly that's changed. Now he mostly hangs out at Katy's place in LA.''