(CNN) -- U.N. Secretary-General Ban Ki-moon said the "political stalemate" in the Ivory Coast could lead to fighting, and he repeated his call for the incumbent to leave office after losing the presidential runoff election last month.
"The situation is taking a worrying turn with unfolding events that could lead to widespread violence," Ban said in a statement Wednesday.
The developments include the recent threats by some commanders of the national security forces to resort to military options and clashes on Monday between security forces and ex-rebels supporting the internationally recognized winner of the election.
Ban reiterated his call on all parties "to exercise patience and refrain from any actions that could, accidentally or deliberately, provoke violence." He said in the "currently charged political environment such actions could have unpredictable consequences, including reigniting civil war."
Alassane Ouattara, a former economist for the International Monetary Fund who served as prime minister, was named the winner of a November presidential runoff by Ivory Coast's Independent Electoral Commission.
But the country's Constitutional Council promptly invalidated those results and declared incumbent President Laurent Gbagbo the winner.
Gbagbo has already been sworn in for a new term, even though several international organizations have called on him to step down and cede power to Ouattara.
Ban reiterated his call for "Gbagbo to respect the will of the Ivorian people, democratically expressed through the run-off presidential election, and to step down to allow President-elect Ouattara to assume his mandate."
The secretary-general said he is in "close contact" with Ivorians and world leaders "who stand firm in their demand for a peaceful end to the crisis and for respect for the will of the people."
"Those who incite or perpetrate violence and those who use the media for this purpose," Ban said, "will be held accountable for their actions."
Once a prosperous nation and a driving force in West Africa, the Ivory Coast spiraled into instability and civil warfare, as fighting erupted between the government-held south and discontented Muslim rebels living in the north. Thousands were killed.