US hip-hop star Jay-Z has been reunited with his protege Rihanna at BBC Radio 1's Hackney Weekend.

The Talk That Talk singer, who is headlining the music festival on Sunday, made a surprise appearance with the rapper - her mentor - on their hit Run This Town.

Jay-Z, whose real name is Shawn Carter, topped the star-studded bill at the Hackney marshes in east London, where other star performers included American musicians like Nicki Minaj, Will.i.am and Jack White as well as home-grown talent such as Leona Lewis, Example, Rizzle Kicks, Ed Sheeran and Michael Kiwanuka.

Closing the day's event, Jay-Z performed past hits like 99 Problems, Bonnie & Clyde and Girls, Girls, Girls.

As well as Rihanna, Jay-Z was also joined by Kanye West, whom he collaborated with on their album Watch The Throne. They performed a rousing and crowd-pleasing rendition of N****s In Paris twice and No Church In The Wild together.

MIA encountered problems with her microphone when she made a cameo appearance on stage in between Jay-Z's set to perform two songs including Paper Planes. She later thanked fans for alerting her to the issue.

Lewis, who grew up in Hackney, earlier spoke of her pride at performing on her home ground to open the BBC's biggest free live event.

The X Factor winner said backstage: "I really wanted to open when they asked me to do it.

"When I went on I saw 30,000 people running towards the stage. It was lovely performing in front of a home crowd. It was good, I swear half the audience was my friends and family."

Some 50,000 attended the gig on Saturday, with another 50,000 expected to be present on Sunday. Rihanna, Plan B and Florence + The Machine are among the acts performing on Sunday.