West African leaders met in a summit on Wednesday under pressure to take action over Ivory Coast with Laurent Gbagbo defying their earlier threats to use force and the country's crisis deepening.

Nigerian President Goodluck Jonathan, the current chairman of west African bloc ECOWAS, said the two-day summit would consider whether to urge the United Nations to take further action on the crisis, but did not provide specifics.

"I believe we can pass a resolution to request the UN to take a little more serious steps on the Cote d'Ivoire situation," Jonathan said of the 15-nation Economic Community of West African States, whose summit ends Thursday.

He also said at the summit opening: "I have no doubt we have the will, the commitment and the collective resolve to bring to an end the unfortunate crisis in Cote d'Ivoire, hopefully without resort to use of legitimate force."

The talks at a hotel in the Nigerian capital Abuja come three months after ECOWAS held an emergency summit at which they threatened to use force if Ivorian strongman Gbagbo did not step down peacefully.

Gbagbo, deemed by his country's election authority to have lost November polls, has remained defiant and Ivory Coast teeters on the brink of civil war.

ECOWAS has recognised Gbagbo's rival Alassane Ouattara as president, as much of the world has also done, and suspended Ivory Coast from the bloc. But the potential use of force seems to have been put on the back burner.

"Events in the country in the last few weeks are very worrying," AU chief Jean Ping said in a speech read on his behalf by his chief of staff John Shinkaiye.

"Violence is escalating. I urge that the opportunity of your summit be taken to again implore Mr. Laurent Gbagbo to do what is right for his people and his country," Ping said.

The AU leader had to skip the summit to address crises in northern Africa, notably in Libya.

Asked at what point force would have to be used in the Ivorian crisis, Shinkaiye told AFP that "I cannot speculate on that."

"All I can say is that both ECOWAS and the AU agree that the use of force will be our last resort after every other peaceful means have failed," he said.

According to the United Nations, at least 440 people have been killed in the unrest since the presidential vote.

UN Secretary General Ban Ki-moon's special representative for west Africa, Said Djinnit, said at the summit opening that the UN peacekeeping force in Ivory Coast was facing an increasingly dangerous job.

Both Djinnit and Ping spoke of the imminent appointment of an African Union high representative to follow up on recommendations from a panel of African leaders on resolving the crisis.

The ECOWAS summit, attended by the presidents of Liberia, Senegal, Benin, Mali, Togo, Cape Verde, Sierra Leone and Burkina Faso, as well as representatives from other nations, went behind closed doors after the opening speeches.

Officials familiar with the talks said a statement on Ivory Coast was expected on Thursday.

Earlier, about 100 women protested outside the ECOWAS headquarters in Abuja to urge an end to the violence in Ivory Coast.

One of them, an Ivorian, was allowed to address the summit opening, and she broke down in tears as she pleaded with the leaders.

"The stakes are high, the casualties are increasing and the eventual outcomes might have regional consequences," Salimata Porquet said. She highlighted the recent killing of seven women protesters in the country.

Earlier this week, Nigerian Foreign Minister Odein Ajumogobia lashed out at the international community, saying the world's focus had moved to Libya as the crisis worsened in Ivory Coast.

Ajumogobia has said the United Nations must endorse any use of force to remove Gbagbo, adding that a blockade was an option if peaceful efforts fail.

That has raised questions over whether such a measure would face opposition at the UN Security Council from countries such as China or Russia.

The ECOWAS summit will also review their suspensions of Guinea and Niger, both of which recently held elections to transfer power from military regimes.