France called yesterday on other world powers to commit money and logistical support to African armies readying their troops to join French soldiers already battling al-Qaeda-linked militants in Mali.

The appeal came as African leaders met in Ivory Coast, where they are expected to agree details of a regional mission due to take over from French forces – but it is short on financing, planning and even ammunition.

France has deployed ground troops and its war planes have bombed a rebel column, halting an Islamist advance. The intervention is aimed at stopping militants from tightening their grip on Mali's northern desert zone and using it as a springboard for attacks in Africa and on the West.

The stakes rose dramatically last week when Islamist gunmen cited the French intervention as a pretext to attack a desert gas plant in neighbouring Algeria and seize hostages. The Sahara crisis has forced African nations to accelerate their own planned mission to Mali, which was originally not expected to be in place before September.

French foreign minister Laurent Fabius said French troops were in no way intended to replace the African operation.

"We must, as quickly as possible, furnish the logistical and financial means required," he said, calling on donors to make commitments at a January 29 conference in Ethiopia.

Mali's north has been occupied by a mix of gunmen since rebels bolstered with weapons seized from Libya after the 2011 fall of Muammar Gaddafi took up arms last year.

Separatist Tuareg rebels who launched the fighting were soon sidelined by the Islamist alliance of al-Qaeda's North African wing AQIM and homegrown Malian groups Ansar Dine and MUJWA.

Heads of state are expected to formally confirm pledges to dispatch about 5000 African soldiers to join French forces in Mali.

Ivory Coast president Alassane Ouattara said: "We must intervene because no economic revival, no region in the world will be safe if the Sahel [region] goes over to the wrong side."

Nigeria and Togo have already started their deployments, with Niger, Burkina Faso and Chad expected soon. But a Western diplomat following the process said plans for the mission were "fluid".

"The troops are meant to go with 10-day self-sufficiency. But there's nothing in place to say what happens after," the diplomat said. "Who's going to pay for this, and what mechanisms are going to pay for it? The money is a big question."

Underscoring the scale of the challenge, two other diplomats said that Senegal's deployment was being held up by the lack of ammunition for their artillery.

"They are waiting for it to be delivered," said one.

French president François Hollande, who ordered French fighter jets into action in Mali a week ago to halt the Islamist advance, said yesterday that France's military intervention will last as long as it takes to overcome terrorism in the region.

"People often ask how long this will last. I reply, the time it takes. The time it takes to vanquish terrorism in this area," he insisted.