Jay Z has performed for thousands of music fans in New York's Central Park and encouraged the crowd to help end world poverty.

The rap star headlined the Global Citizen Festival on the Great Lawn, where Beyonce surprised the audience by performing with her husband.

He told the crowd of 60,000 - many of whom earned free tickets by volunteering - to support the Global Citizen Festival's effort to end poverty by 2030.

"We out here for a good cause," he said onstage. "I want to thank everybody out here for this good movement."

Dressed in all black, Jay Z wore a hoodie with the Global Citizen Festival's logo and the names of other headliners, including Carrie Underwood, The Roots, Alicia Keys, Tiesto, fun. and No Doubt, who brought out special guest Sting to perform Message In A Bottle, a crowd favourite.

Jay Z's electrifying set opened with audio from Frank Sinatra's New York, New York and Billy Joel's New York State Of Mind. The Brooklyn-born rapper then went into his own New York anthem, Empire State Of Mind, and followed it with his rich catalogue of hits, from Big Pimpin to 99 Problems.

He left the stage, but moments later the crowd roared as Beyonce entered alongside her husband. She sang the choruses from his songs Holy Grail - where she danced excitedly - and Forever Young as the audience cheered and sang along.

The concert marked another New York venue that Jay Z - hip-hop's most powerful voice - has performed in. He has had numerous sold-out shows at Madison Square Garden, where he held a September 11 benefit show in 2009, and he is one of a few rap acts to perform at Carnegie Hall. He opened the Barclays Centre in Brooklyn with eight consecutive shows in 2012.

The Global Citizen Festival coincides with the UN General Assembly meeting. Indian Prime Minister Narendra Modi and UN Secretary-General Ban Ki-moon were among the world leaders who attended in support of the anti-poverty campaign.

Hugh Jackman hosted the third annual event, which also featured Olivia Wilde and Jessica Alba and aired on MSNBC. Stevie Wonder headlined the festival last year, and Neil Young and Foo Fighters were among the line-up it its inaugural year.