Incumbent President Laurent Gbagbo refuses to hand over power despite international recognition that Alassane Ouattara won a November presidential election meant to unite a country divided by civil war in 2002.
Y.J. Choi, the U.N. envoy to the Ivory Coast, said his team needed to stay active in the country to prevent the political turmoil from spiraling out of control.
Peacekeepers with the U.N. mission Abidjan are guarding the hotel stronghold of Ouattara. Choi said tensions meant Ouattara and the U.N. forces might have to move to Bouake, a city in the north of the country where Ouattara draws his support.
"(T)hat would mean the division of the country and perhaps the resumption of the civil war," he said in a statement.
Political violence in the Ivory Coast has displaced around 50,000 people and left at least 300 people dead. Gbagbo has called on all 9,000 troops with the U.N. peacekeeping force to leave the country. The U.N. Security Council last month, however, authorized the use of force in the country through a Chapter VII mandate.
African leaders said they were also considering force to pressure Gbagbo to step down.