Pop stars Katy Perry, Bruno Mars and Chris Martin helped Rihanna celebrate her birthday one week early during a Barbados-themed bash on Monday.

The "Umbrella" hitmaker doesn't officially turn 24 until next week but she got the party started with more than 100 friends and family members at the Hearst Mansion in Beverly Hills, California.

Guests including Coldplay frontman Martin and gal pal Perry feasted on a Caribbean-style dinner - as a tribute to Rihanna's island roots - and indulged in cupcakes decorated with Barbadian flags.

A brass drum player was also on hand to play reggae tunes and a guest tells People.com, "Rihanna was dancing all night and had an amazing time celebrating with her friends."

Towards the end of the evening, a personalised birthday cake, featuring an image of a bikini-clad Rihanna, was brought out along with more than 20 bottles of champagne for a special toast. Attendees also walked away with high-end Camacho cigars as a parting gift.