(CNN) -- President Barack Obama urged the disputed leader of Ivory Coast to step down to prevent more violence as the nation grapples with postelection clashes that have left hundreds dead.
"Last year's election was free and fair, and President Alassane Ouattara is the democratically elected leader of the nation," Obama said in a video message late Friday.
The west African nation has been embroiled in a political stalemate since incumbent leader Laurent Gbagbo refused to step down after November elections.
Election officials and the international community consider Ouattara the rightful winner of the poll.
Obama warned that if Gbagbo does not step down, it will lead to "more violence, more innocent civilians being wounded and killed, and more diplomatic and economic isolation."
Postelection clashes have left at least 462 dead since December, according to the United Nations.
Escalated violence and fears of war have forced nearly 1 million residents to flee the commercial capital, the U.N. refugee agency said Friday, with scores more uprooted across the country.
"The massive displacement in Abidjan and elsewhere is being fueled by fears of all-out war," said Melissa Fleming, a spokeswoman for the U.N. High Commissioner for Refugees.
Clashes have raged since late last year, and analysts fear the country is on the brink of a civil war.
The nation was once one of Africa's success stories, but a 2002 civil war plunged it into political instability.
"You have a proud past from gaining your independence to overcoming civil war, now you have the opportunity to realize your future," Obama said.
Ivorians deserve leaders who can restore their rightful place in the world, the president said.
Obama's message comes after the U.N. Security Council discussed a draft resolution introduced by France and Nigeria on a weapons ban in Abidjan. It also calls for sanctions against Gbagbo and his inner circle.
Numerous attempts to resolve the political stalemate have failed because Gbagbo has refused to cede power, said Gerard Araud, the French ambassador to the United Nations.
CNN's Faith Karimi and Moni Basu contributed to this report.