Witnesses and a UN official say the Golf Hotel in Abidjan had come under mortar and small-arms fire, and the UK embassy has been evacuated.

Alassane Ouattara was judged to have won the presidential election, but Mr Gbagbo has refused to step down.

He has been surrounded in his residence for days by pro-Ouattara troops.

Reports suggested Saturday's fighting flared at around 1700 GMT.

Mr Ouattara's forces have swept down from the north of Ivory Coast over the past two weeks but much of Abidjan is dominated by Gbagbo supporters. Days of fighting have plunged the city into crisis.

An estimated one million people have been made homeless by the recent fighting, and there are growing concerns for public health.