Alassane Ouattara, whom the United Nations and Ivory Coast’s own electoral council declared the winner of November presidential elections, said the forces backing him will “re-establish democracy and enforce the choice of the people.” “Today they are at the doorstep of Abidjan,” Ouattara said of his armed supporters. “To all those who are still hesitating, whether you are generals, superior officers, officers, sub-officers, rank-and-file ... there is still time to join your brothers-in-arms.” Incumbent Laurent Gbagbo has refused to step down and recognize the result of the election. But even an armed onslaught on the country’s commercial capital will not force him to do so, said Toussaint Alain, one of his advisers.

“He will not resign in the wake of this attack. He is not going to abdicate. He is not going to lay down his arms,” Alain said. “He will stay in power to lead the resistance to this attack against Ivory Coast organized by France, the United States and the United Nations.” Gbagbo hasn’t been seen in public for weeks, even though state TV announced twice on Wednesday evening that he was preparing to address the nation. Ivory Coast’s army chief of staff, Gen. Phillippe Mangou, sought refuge at the home of the South African ambassador in Abidjan with his wife and five children, South Africa’s foreign ministry said Thursday.

Advancing on foot while firing into the air, pro-Ouattara forces set up roadblocks on one of the main thoroughfares in Yopougon, a neighborhood across the lagoon from the presidential palace. They have been in a pitched battle with police since 6:30 a.m. Thursday, said a local resident who asked not to be named for fear of reprisals.

“The end is almost here. It’s a matter of hours,” said Patrick Achi, spokesman for Ouattara. “We issued our ultimatum yesterday ... If Gbagbo does not want the fighting to happen in Abidjan, he should surrender. If he doesn’t, we have no choice.” It is not clear what the fighters will do if they manage to push their way to the presidential palace, located on a peninsula in the city center, surrounded on all sides by a glassy lagoon. In the early afternoon a column of smoke could be seen coming from several neighborhoods.

Shooting rang out from the base of one of the two bridges that spans the lagoon, offering access to the peninsula.

Taxis made panicked U-turns on the waterside highway.

The fighters’ arrival in Abidjan comes only a day after they seized the administrative capital of Yamoussoukro in central Ivory Coast. Pro-Ouattara forces also took the strategic port of San Pedro late Wednesday, and by one estimate now control about 80 percent of the country.

Ouattara has described his fighters as the “Republican Forces.” The majority of the gunmen are drawn from the New Forces, a coalition of rebel groups that fought a brief 2002-2003 civil war, which left the country divided in two with the rebels holding the north.

“In order to end the escalation of violence in our country and in keeping with their mission to protect the population against militias and mercenaries under Gbagbo’s control, (the rebels) have decided to re-establish democracy and enforce the choice of the people,” he said.

The rebels have seized more than a dozen towns since beginning their offensive on Monday. After they took the capital, they did a victory lap in vehicles as people cheered and clapped.

They have faced almost no resistance but many fear that army troops still loyal to Gbagbo plan to make a final stand in Abidjan. But Ouattara’s forces could confront fierce resistance in densely populated Abidjan, which is dangerously divided between those who support him and those who back Gbagbo.

The two men have vied for the presidency for months, with Ouattara using his considerable international clout to try to financially and diplomatically suffocate Gbagbo. At least 462 people have been killed and up to 1 million have fled their homes amid the postelection chaos.

The advance by pro-Ouattara forces was a last resort after all other diplomatic means had failed, his supporters say.

Ouattara won the election with more than 54 percent of the vote and did not want to be seen as having taken the country by force.

So far, the rebels appear to be mostly disciplined although there have been sporadic reports of pillaging and several instances of revenge killings. His reliance on the irregular fighters could cause him to lose the moral high ground if they begin committing serious abuses.

Human Rights Watch documented attacks on villages, rapes and racketeering in the country’s north, where they exercised control.

Overnight the fighters took the port of San Pedro, giving Ouattara access to the sea. They also reached Mama, the village where Gbagbo was born and where he built himself a mansion. It marked a symbolic victory, said Seydou Ouattara, a rebel spokesman who is not related to the president.

“The rebels slept in Gbagbo’s bed,” he said.