DOUENTZA, Mali (Reuters) - French troops took control on Wednesday of the airport of Mali's northeast town of Kidal, the last urban stronghold held by Islamist rebels, as they moved to wrap up the first phase of a military operation to wrest northern Mali from rebel hands.
A three-week ground and air offensive by French forces aimed at initially ending a 10-month Islamist rebel occupation of major towns is expected to eventually hand over to a larger African force.
The Africans' task will be rooting out insurgents hiding in the desert and mountains near Algeria's border.
"They (the French) arrived late last night and deployed in four planes and some helicopters," Haminy Belco Maiga, president of Kidal's regional assembly of Kidal, told Reuters.
However, the deployment of French troops to remote Kidal puts them in direct contact with pro-autonomy Tuareg MNLA rebels operating there.
The Tuaregs, whose separatist rebellion last year was hijacked by the Islamist radicals, say they are ready to fight al Qaeda, but many Malians blame them for triggering the collapse of democracy and division with their northern revolt.
France's military operation in its former West African colony involves around 3,500 troops on the ground backed by warplanes, helicopters and armoured vehicles. It is aimed at heading off the risk of Mali being used as a springboard for jihadist attacks in the wider region or Europe.
French and Malian troops retook the major Saharan trading towns of Gao and Timbuktu at the weekend.
There were fears that many thousands of priceless ancient manuscripts held in Timbuktu, a UNESCO World Heritage site, might have been lost during the rebel occupation, but experts said the bulk of the texts were safe.
The United States and European governments strongly support the Mali intervention and are providing logistical and surveillance backing but do not intend to send combat troops.
The MNLA rebels, who want greater autonomy for the desert north, said they had moved fighters into Kidal after Islamists left the town earlier this week.
"For the moment, there is a coordination with the French troops," said Moussa Ag Assarid, the MNLA spokesman in Paris.
There were no reports of Malian government troops being in the town.
The MNLA took up arms against the Bamako government a year ago, seeking to carve out a new independent desert state.
After initially fighting alongside the Islamists, by June they had been forced out by their better armed and financed former allies, who include al Qaeda North Africa's wing, AQIM, a splinter wing called MUJWA and Ansar Dine, a Malian group.
But as the French wind up the successful first phase of their offensive, doubts remain about just how quickly the U.N.-backed African intervention force, known as AFISMA and now expected to exceed 8,000 troops, can be fully deployed in Mali to hunt down the retreating al Qaeda-allied insurgents.
French Foreign Minister Laurent Fabius said the French military operation, codenamed Serval (Wildcat), was planned to be a lightning mission that would last just a few weeks to avoid getting bogged down.
"Liberating Gao and Timbuktu very quickly was part of the plan. Now it's up to the African countries to take over," he told the Le Parisien daily. "We decided to put in the means and the necessary number of soldiers to strike hard. But the French contingent will not stay like this. We will leave very quickly."
Fabius warned that things could now get more difficult, as the offensive seeks to flush out insurgents with experience of fighting in the desert from their wilderness hideouts.
"We have to be careful. We are entering a complicated phase where the risks of attacks or kidnappings are extremely high. French interests are threatened throughout the entire Sahel."
An attack on the In Amenas gas plant in Algeria earlier this month by Islamist fighters opposing the French intervention in Mali led to the deaths of dozens of foreign hostages and raised fears of similar reprisal strikes across North and West Africa.
While the French operation has made destroying Islamist fighters, positions and assets with air strikes a priority, analysts say a long term solution for Mali hinges on finding a political settlement between the northern communities and the southern capital Bamako.
Interim President Dioncounda Traore said on Tuesday his government would aim to hold national elections on July 31.
After months of being kept on the political sidelines, the MNLA said they were in contact with West African mediators who are trying to forge a national settlement to reunite Mali.
"We reiterate that we are ready to talk with Bamako and to find a political solution. We want self-determination, but all that will be up to negotiations which will determine at what level both parties can go," Ag Assarid said.
However, there have been cases in Gao and Timbuktu and other recaptured towns of reprisal attacks and looting of shops and residences belonging to Malian Tuaregs and Arabs suspected of sympathising with the MNLA and the Islamist rebels.
France has called for international observers to be deployed to ensure human rights abuses are not committed.
"Reconciling the Tuaregs with their Malian co-citizens will be extremely complicated," said Francois Heisbourg, a special adviser at the Foundation for Strategic Research, a Paris-based think-tank.
Additional reporting John Irish and Emmanuel Jarry in Paris, David Lewis and Pascal Fletcher in Dakar; Writing by David Lewis; Editing by Pascal Fletcher