Irish rockers U2 were among the early winners at the MTV Europe Music Awards on Thursday, picking up the best live act award hours after treating 10,000 fans to a free concert in front of Berlin's Brandenburg Gate.

The music channel's annual awards ceremony, one of the biggest nights in the pop music calendar outside the United States, is being held in the city to mark the 20th anniversary of the fall of the Berlin Wall.

The wall, a symbol of the Cold War that split the city, was opened on November 9, 1989, leading to the reunification of east and west Germany 11 months later.

U2 performed a handful of hits including One, Sunday Bloody Sunday and Beautiful Day during their 30-minute set.

Berlin, du bist wunderbar, said lead singer Bono, greeting the crowd in German. Hours later he was at the O2 World concert venue to pick up his prize.

U.S. hip hop star Jay-Z was named best urban act. Wearing a black leather jacket and sunglasses, he told the audience of thousands of screaming fans: I look forward to the day when all those walls come down.

His wife, pop singer Beyonce, took to the stage after her husband's acceptance speech, appearing in a red heart and wearing a scarlet bodice and garters to perform the hit Sweet Dreams.

She won the prize for best song for Halo, and Californian punk rockers Green Day scooped the best rock category.

CABARET THEME

U.S. singer Katy Perry, hosting the awards for the second year in a row, had promised a show inspired by the Cabaret film with Liza Minnelli, set in 1930s Berlin, and did not disappoint.

She appeared on stage in a bowler hat, bow tie, bodice and thigh-high boots, and performed a routine on chairs with eight cabaret dancers as glitter rained down on the stage.

As the early awards underlined, the MTV Europe awards which are decided by millions of online votes tend to be dominated by big U.S. names.

This year, New Yorker Lady Gaga and Nashville-based Kings of Leon led the way with five nominations apiece, followed by compatriot Beyonce with four. Detroit rapper Eminem and Green were each shortlisted for three awards.

European acts U2, Pixie Lott and La Roux received two nominations apiece.

Beyonce