(CNN) -- The Malian president announced plans to hold elections by July as French-led troops battled Islamists in the last major northern town under militant control.

A battle is under way to secure Kidal, the last major town in the sweep to flush out militants in the north.

The French military said it seized the airport in Kidal on Tuesday night, thus gaining control of a major point of access.

French forces are focusing on recapturing airports while Malian forces take over the cities, French army spokesman Col. Thierry Burkhard said.

Mali's former colonial power, France, is leading the offensive in the north.

As troops made gains in the region, the French Defense Ministry hailed President Dioncounda Traore's transition plan as a crucial step forward.

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"France welcomes the unanimous adoption by Mali's parliament of the road map for the transition, which makes provision for the holding of elections and the opening of negotiations with the north," the Defense Ministry said in a statement.

It urged Malian authorities to involve legitimate representatives of the north in dialogue to ensure its faster return to normalcy after a tight Islamist grip.

France sent troops at Mali's request after Islamists seized the strategic town of Konna on January 10.

The town is now back in Malian control. Its capture raised fears that militants would turn the vast region into a haven for terrorists.

French-led troops now control the cities of Timbuktu and Gao, along with the swath in between that was an Islamist stronghold for almost a year, the French Defense Ministry said this week.

"The French troops are being vivacious at Kidal airport, which was taken a little more than a day ago," said Jean-Yves Le Drian, the French defense minister. "The weather conditions are such that the complement of the forces will take a bit more time to arrive, but that's part of the risks of the desert."

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Islamic extremists carved out a large portion of northern Mali last year, taking advantage of a chaotic situation after a military coup.

They banned music, smoking, drinking and watching sports on television, and destroyed historic tombs and shrines in the region.

But with the French-led offensive sending the militants on the run, residents are once again roaming the streets without fear.

France has 2,150 soldiers in Mali and 1,000 more troops supporting the operation from elsewhere. West African forces are expected to battle the militants alongside French troops.