Rihanna was the surprise guest at Kanye West’s headlining performance at a Los Angeles music festival.

The Diamonds singer, who had been holidaying in Barbados, gave music fans a shock when she appeared on stage to sing the chorus to FourFiveSeconds – their collaboration with Sir Paul McCartney – at the FYF festival at the weekend.

She was introduced on stage by Kanye, who said: “I need my family to help me out about now.”

Wearing an oversized hoody with her curly hair tied in a ponytail, Rihanna remained on stage at the LA Sports Arena and Exposition Park to perform All Of The Lights with Kanye.

Kanye, who filled in for Frank Ocean after he pulled out days before the festival started, performed a set packed with older hits and new tracks including Jesus Walks, Touch The Sky and Gold Digger, although he didn’t preview any songs from his upcoming new album Swish.

The rapper, who headlined this year’s Glastonbury festival, also brought on his GOOD Music signee Travis Scott, who grabbed the mic for a rendition of Antidote.