Rihanna and Chris Brown engagement rumours refuse to go away - after the pop beauty was snapped sporting a huge diamond ring on her wedding finger.

The pair took to the stage at Elton John's New Year's eve party at London's O2 Arena on Wednesday (31stDec08) to perform a duet, according to Britain's The Sun newspaper.

And the Bajan beauty fuelled speculation of an impending engagement announcement when she was spotted showing off a huge rock in a pair of fingerless leather gloves at the event.

Rihanna and Brown have frequently refused to confirm they are an item - despite Internet gossips recently claiming the rumoured couple were living together.