According to Reuters, security forces have been deployed heavily around the election commission's office in the main city of Abidjan, which was blocked off with a barrier.

Journalists who had been waiting for results inside the building were told to leave, two separate witnesses said.

The United Nations says the poll has been democratic despite some irregularities and Gbagbo's challenge to results in the rebel-held north, where his rival, Alassane Ouattara, did well in the first round.

Ouattara's party has not contested the still unpublished results.

Sunday's vote is intended to heal the north-south divisions that have dogged the world's top cocoa grower since a 2002-2003 civil war. The first main batch of results from the run-off had been due on Tuesday morning.

The results did not emerge and the election commission was not reachable for comment.
Several cocoa exporters said they had shut down operations. Farmers last week had rushed through deliveries in advance of the vote, and supplies this week are seen scant.