US president Barack Obama says the United States recognises Alassane Ouattara as the rightful leader of the west African nation of Ivory Coast.

Many observers argue that Laurent Gbagbo's refusal to cede power to internationally recognised president Alassane Ouattara has pushed the country to the brink of civil war.

"Last year's election was free and fair," Mr Obama said in a video message to the leaders and people of Ivory Coast. "And president Alassane Ouattara is the democratically elected leader of the nation."

The message came after the UN Security Council met to discuss a draft resolution introduced by France and Nigeria on a weapons ban in Abidjan.

Mr Obama says the United States would continue to seek a peaceful transition of power in Ivory Coast and would be a partner of those who chose democracy.

He says the people of Ivory Coast deserved "a future of hope, not fear" and it was time for democracy to triumph in the west African nation.

"You deserve leaders like President Ouattara, who can restore your country's rightful place in the world," he said.

"And those who choose that path will have a friend and partner in the United States of America."

Fighting with heavy weapons raged in two northern suburbs of Abidjan yesterday near a military barracks where pro-Gbagbo forces said they had repelled an attack by rebels backing Mr Ouattara.

As many as 1 million people have fled their homes as civilian areas are bombarded daily with rockets, mortars and shells.

The UN estimates clashes between forces backing the two rivals killed 52 people in the past week, with the total death toll reaching at least 462.

The draft UN resolution demands an end to attacks against the UN mission and civilian populations by Mr Gbagbo's supporters and calls for UN forces to protect civilians, according to one diplomat.

Mr Obama warned that if Mr Gbagbo and his supporters continued to cling to power, it would "lead to more violence, more innocent civilians being wounded and killed and more diplomatic and economic isolation."

White House officials said the international community was united in recognising Mr Ouattara as the duly elected leader of Ivory Coast.

The African Union, the Economic Community of West African States, and the UN Security Council have all repeatedly called for Mr Gbagbo to step aside, the officials said.

- AFP