The U.N. Security Council is not ready to agree to an African Union request for endorsement of military intervention in Mali, where rebels and Islamist militants have seized control of much of the country, council diplomats said on Friday.

"It's going to take some time before the Security Council is in a position to approve outside intervention in Mali," a council diplomat said on condition of anonymity.

"It's not that we're opposed, it's just that there are many questions about how it would be done that need to be answered first."

Mali, once regarded as a good example of African democracy, collapsed into chaos after soldiers toppled the president in March, leaving a power vacuum that enabled Tuareg rebels from the north to take control of nearly two-thirds of the country.

The uprising also involved both local and foreign Islamist militants, and Western diplomats talk of the risk of the country turning into a 'West African Afghanistan'.

The African Union said on Tuesday it had asked the U.N. Security Council for a resolution that would allow military intervention in Mali.

The Economic Community of West African States (ECOWAS), an umbrella group of 15 countries aimed at promoting regional cooperation, says it is ready to organise military intervention to restore constitutional order in the country, but wants a U.N. Security Council mandate and U.N. support.

Earlier this week the U.N. Security Council met informally with members of African Union's Peace and Security Council. They issued a declaration afterwards that stopped short of giving ECOWAS a green light to intervene in Mali.

The statement said the two bodies "acknowledge the efforts of ECOWAS to explore options to restore peace and security in Mali in the context of upholding Mali's territorial integrity."

Speaking after another informal meeting between council members and the African Union on Friday, diplomats said they need to know more about how an ECOWAS military operation would be mounted before they agree to endorse it.

PLANNING UNDERWAY

Diplomats said ECOWAS needed to show it had the troops, credible objectives and a sound strategy to conduct an operation. There are also questions about funding.

"They don't have anything," one senior council diplomat said. "It's ridiculous."

Another question that needs to be answered, diplomats said, is what an ECOWAS force would do in northern Mali with the Tuareg and Islamist militants believed to be linked to al Qaeda.

"Those guys are tough in the North," another diplomat said. "I'm not sure ECOWAS is up to it yet."

"Are they (ECOWAS) going to go in fighting?" another asked.

Of the 15 council members, France, Morocco and Togo were among the most enthusiastic about swiftly endorsing an ECOWAS operation in Mali, envoys said. Others are more skeptical.

ECOWAS has intervened militarily in past African conflicts, such as the wars in Liberia and Sierra Leone.

Salamatu Hussaini Suleiman, ECOWAS commissioner for political affairs, peace and security, told reporters after Friday's African Union-Security Council meeting that talks on military intervention in Mali were 'at the planning stages'.

But she said ECOWAS was "indeed requesting the United Nations Security Council to pass a resolution that will legitimize any action, any military action, that we're going to take in Mali and that is what we are pursuing."

"ECOWAS have given a mandate for 3,000 (troops) to be put on standby," she said, adding that there was a planning conference underway in Abidjan, Ivory Coast and ECOWAS was working with U.S., French, U.N. and other experts to prepare a strategy.

Suleiman said the council's response to ECOWAS' proposal on Mali had so far been 'very, very positive' and predicted it was likely to adopt a resolution endorsing ECOWAS action 'very soon'.