Paris Hilton throws surprise birthday bash for Chris Zylka

Paris Hilton celebrated her boyfriend Chris Zylka's 32nd birthday on Saturday (13May17) by throwing him a surprise party with guests including Katy Perry and Iggy Azalea.

The hotel heiress played hostess at the bash, which was held at her Beverly Hills mansion, in a lavish room decked out as a nightclub, fittingly titled Club Paris, reports UsMagazine.com.

She and the birthday boy also partied the night away with pals including actress Bella Thorne, American football star Odell Beckham, Jr., and model Sofia Richie, the younger sister of Paris' The Simple Life co-star and former best friend Nicole Richie.

Pop star Katy documented her visit in a series of video clips on Instagram as she marvelled at the socialite's giant dog house and hung out with her furry friends, while the singer also shared footage of herself idolizing a massive mosaic of Paris, which she captioned, "The realest queen in the game".

"Waking up to this today made my day," responded Paris on Sunday morning (14May17). "Love you @KatyPerry! You are such a beautiful magical #Queen!"

Paris, 36, also shared her own recap of the party in a series of photos taken with her famous friends.

"Last night was #LitAF!," she exclaimed. "Had the best time with my beautiful girls @TheNewClassic (Azalea) @SofiaRichie @KatyPerry @BellaThorne @ChiaraFerragni. #GirlPower".

The star and The Leftovers actor Chris went public with their budding romance in February (17), and Paris is adamant he is 'The One'.

"(We're) soulmates, for sure, 100 per cent," Paris gushed to Entertainment Tonight earlier this month (May17). "(Being soulmates is) just being best friends and finally finding someone that I love and trust and know that I want to spend the rest of my life with. It's the best feeling in the world."