Robert Pattinson joins Justin Bieber to party with Katy Perry

Robert Pattinson made a surprise appearance at Katy Perry's Part of Me after-party

Robert Pattinson, Katy Perry, Justin Bieber and his girlfriend Selena Gomez all partied together in Hollywood on Tuesday night.

We knew Pattinson had become close friends with Perry ever since her split with Russell Brand, but we would never have put the Twilight hunk down to be chums with teeny boppers Bieber and Gomez.

Nevertheless, Pattinson and his celeb friends met up at LA hotspot Chateau Marmont to celebrate Perry's Part of Me premiere before all piling into Bieber's $200,000 Mercedes Benz minivan and travelling to the opening of David Arquette's new club, Bootsy Bellows.

KATY PERRY HITS THE RED CARPET FOR PART OF ME PREMIERE

Robert Pattinson's girlfriend, Kristen Stewart, was notably absent from the party because she's due to attend a Balenciaga event in Paris and as been jetting all over the globe to promote Snow White and the Huntsman.

Despite their busy schedules, the Twilight couple did get to spend some time together over the weekend at the wedding of Hollywood producer Kevin Turen and Evelina Oboza in New Jersey. 

Robert and Kristen joined Zac Efron and Andrew Garfield at the nuptials, where onlookers reported the pair as being very loved up.

Cute!

Watch Robert Pattinson, Katy Perry and Justin Bieber clubbing below...

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