Abidjan, Jan 11 (Agencies): Former Nigerian leader and mediator Olusegun Obasanjo left Ivory Coast early on Monday as the country's incumbent President continued to defy the world and insist he had won the recent election.

Obasanjo had driven back and forth between the presidency and a hotel across town where the internationally recognised winner Alassane Ouattara is barricaded.

Three other high-level delegations, including a mission last week by several African heads of State, have all failed to get sway incumbent Laurent Gbagbo to cede power.

In a statement late on Monday, the UN Security Council welcomed plans by the African Union and the West African regional group ECOWAS to send another high-level delegation "as soon as possible" to try to achieve a peaceful solution to the crisis in Ivory Coast.

The council expressed deep concern at continued violence and human rights violations in Ivory Coast, including against peacekeepers, and condemned attempts to prevent the UN force from protecting civilians and investigating atrocities.

Foreign embassies have ordered a majority of their staff to leave as anti-Western sentiment simmers. Gbagbo's regime continues to use the State broadcasting arm to denounce the "Franco-American plot" behind calls for his ouster.

On Monday, the US Embassy held a meeting with American citizens and urged them to leave while commercial flights were still available, warning that the embassy would not be able to come get them from their homes if widespread violence breaks out.

"Pack your bags—we've packed ours," US Consul Barbara Ensslin said.

The purpose of Obasanjo's visit was to deliver the international community's message as forcefully as possible, and to offer Gbagbo an exile abroad and a monthly stipend if he chooses to step down, said an adviser to Ouattara on condition of anonymity.

He also said the Obasanjo repeated the warning that Gbagbo will face a regional military ouster if he does not cede power. The 15-nation regional bloc ECOWAS has threatened to remove him by force if negotiations fail.

Nigeria remains the lynchpin in the decision to mount a military ouster, since the country has one of the largest standing forces in West Africa.

Obasanjo holds weight in the region because he is a former military leader and voluntarily handed over power in the 1970s to a civilian-led, elected Government.

He has also been a top mediator, including in Ivory Coast, which had not held an election for 10 years due to a civil war and a subsequent political impasse.