UN troops surround Gbagbo's "last defenders"
France has taken a leading role in talks to persuade Gbagbo to hand over to Ouattara and end the standoff over the contested election in November.
"Gbagbo's fall will happen, inevitably, in, I am not going to say the hours or days ahead, I am cautious," French Foreign Minister Alain Juppe said on Thursday.
Ouattara commander Toure Moussa said talks with Gbagbo's camp were still ongoing, but Juppe appeared to dismiss that.
"This has been going on for four months. When people say we should give time to mediation -- we have given plenty of time to mediation efforts," Juppe said.
Gbagbo, who has refused to recognise Ouattara's victory, said on Wednesday he had no intention of stepping down.
Helicopters from French forces and the United Nations peacekeeping mission in Ivory Coast bombarded Gbagbo's heavy weapons stockpiles earlier this week, including those near his residence.
Analysts said Ouattara forces, who swept south last week in a lightly contested march toward Abidjan, could struggle to best Gbagbo's remaining presidential guard and militias unless they are backed by French and U.N. forces.
Gbagbo has ruled Ivory Coast since 2000 and blames Paris for supporting the north of the country in the civil war of 2002-03. Rebels from that war now make up the bulk of Ouattara's force.
Last year's long-delayed election in the world's top cocoa producing nation was meant to draw a line under the civil war, but Gbagbo's refusal to give up power has plunged the country into violence that has killed more than 1,500 people.
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