American singer Chris Brown has been charged with assaulting a man outside a five-star hotel in the early hours of Sunday morning.

The 24-year-old was charged after the alleged attack in Washington DC, the Metropolitan Police Department said.

If found guilty, he could face a four-year jail term as he is still on parole for assaulting ex-girlfriend Rihanna in 2009.

According to TMZ, the R'n'B star got into an altercation with the man outside the W hotel at about 4.30am and punched him.

Christopher Hollosy, reported to be Brown's bodyguard, was arrested with Brown and faces the same charges.

Earlier, he had hosted a party at the city's Park at Fourteenth club.

The victim was taken to hospital with a broken nose that may require surgery, according to TMZ.

The website claims Brown was not under the influence of drugs or alcohol.

Brown's parole was revoked in the summer when he was involved in a hit-and-run traffic accident in Los Angeles, but reinstated in September when he agreed to do another 1,000 hours community service.

He is due back in LA on 20 November for a probation review.