Auction rivals! Rihanna and Miley splash the cash at amfAR Gala ...as Cyrus spends $500k

They are both rivals when it comes to being divas in the pop world.

And last night it seemed Rihanna and Miley Cyrus had a point to prove as they both went head-to-head to see who could splash the most cash at the amfAR Gala Auction in Los Angeles.

Rihanna was first off, shelling out $35,000 on Harry Winston diamond link earrings featuring 72 diamonds set in platinum and a further $100,000 on the photograph Elizabeth Taylor at the Eden Roc by Willy Rizzo, signed and numbered by the artist. #MORE pics below:

However, Miley beat out her rival by spending an enormous $500,000 in total, at the glitzy event.

After bidding $300,000 on a Ryan McGinley photograph, she said, 'I'm a little drunk'.

She then donated a further $200,000 to the AIDS charity.

Meanwhile, Rihanna also looked deep in conversation with Justin, who was not with his wife Jessica Biel.

Rihanna and Justin have been friends for years, and collaborated together on her album Rated R for the moody track Cold Case Of Love.