French troops seized the airport in Mali’s northern town of Kidal, the last urban stronghold held by Islamist insurgents, as they moved to wrap up the first phase of a military operation to wrest northern Mali from rebel hands.

France has deployed some 4,500 troops in a three-week ground and air offensive to break the Islamist rebels’ 10-month grip on major northern towns. The mission is aimed at heading off the risk of Mali being used as a springboard for jihadist attacks in the wider region or Europe.

The French military plans to gradually hand over to a larger African force, tasked with rooting out insurgents in their mountain redoubts near Algeria’s border.

Defence Minister Jean-Yves Le Drian said French forces using planes and helicopters defied a sandstorm late on Tuesday to capture the airport but had been prevented by the bad weather from entering the town itself.

“The terrorist forces are pulling back to the Adrar des Ifoghas mountains which are difficult to access,” Le Drian told a news conference. “There is support from Chadian and Nigerian troops coming from the south.” 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. As the French wind up the first phase of their offensive, doubts remain about just how quickly the UN-backed African intervention force can be fully deployed in Mali to hunt down the retreating al-Qaeda-allied insurgents.

Known as Afisma, the force is now expected to exceed 8,000 troops.

Foreign Minister Laurent Fabius said France’s military operation, codenamed Serval (Wildcat), was planned as a lightning mission lasting a few weeks.

“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.”

One French soldier has been killed in the mission, and 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.

Sign up to our free newsletters

Get the best updates straight to your inbox:
Please select at least one mailing list.

You can unsubscribe at any time by clicking the link in the footer of our emails. We use Mailchimp as our marketing platform. By subscribing, you acknowledge that your information will be transferred to Mailchimp for processing.