Katy Perry has prepared for her forthcoming wedding to Russell Brand with a swish hen party in Las Vegas, joined by close pal Rihanna.

The I Kissed A Girl singer arrived at Sin City’s Hard Rock Hotel Beach Club pool with a veil tucked in to the back of her bikini bottoms like a train and the group – carrying inflatable novelty hen party items – hung around by the pool sipping champagne, beer and vodka and nibbling canapes, reports.

Katy appeared to be enjoying the drinking session, but later wrote on Twitter: “Signing up for a liver transplant now.”

The 25-year-old California Gurls singer and her friends then took a stretch Hummer limo to watch Cirque Du Soleil.

The group dined at Ago, before heading to XS nightclub where Katy, wearing a sparkling black cocktail dress and miniature top hat with a veil, kept a low profile, sitting at a VIP table with Rihanna.

The party reportedly then moved on to a strip club, where Katy reportedly watched the female strippers dancing to her songs, and she even got a dance of her own from a blonde dancer.

Previously Katy’s fiance Russell, was arrested at Los Angeles airport for allegedly assaulting a photographer as the couple arrived.

Katy tweeted: “If you cross the line and try an put a lens up my dress, my fiance will do his job and protect me. Stand by your man. Don’t f*** with the Brands.”

Russell also took to Twitter to make light of the situation.

“Thanks for all your sweet messages of support. After the tips I picked up in chokey I’m an infinitely more proficient criminal,” he wrote.