French air strikes destroyed the home of the leader of an Al-Qaeda-linked group in northern Mali as French-led forces advanced Sunday on the Islamist stronghold of Timbuktu.

The overnight strikes in Kidal came 24 hours after French-led troops seized Gao, the most populated town in Mali's Islamist-controlled arid north, which is roughly the size of Texas. Gao is home to about 60,000 people.

"There were air raids on Islamist bases in Kidal," 1,500 kilometres (940 miles) north of the capital Bamako, a Malian security source said, adding that the home of Ansar Dine (Defenders of the Faith) chief Iyad Ag Ghaly was destroyed.

A local official and residents gave similar accounts.

Kidal has been a bastion of Ansar Dine, whose leader Iyad Ag Ghaly is a former soldier and a Tuareg ex-rebel, who formed the group last year.

In April last year after a coup in Bamako, an alliance of Tuareg rebels seeking an independent homeland in the north joined forces with several Islamist groups, seizing Kidal first and then the northern towns of Gao and Timbuktu.

The Islamists quickly sidelined the Tuaregs, imposing a harsh version of Islamic sharia law in the region. Transgressors were flogged, stoned and executed, they banned music and television and forced women to wear veils.

France launched a military offensive on January 11 after Islamists captured a central town and pushed deeper into government territory towards the capital Bamako.

French Prime Minister Jean-Marc Ayrault said the troops, having captured Gao, were advancing on Timbuktu, another key town held by Al Qaeda-linked rebels and a centre of Islamic learning for centuries.

Washington meanwhile decided to step up its role in the conflict by helping refuel French warplanes.

Washington's decision to agree to France's request for air refuelling facilities came after two weeks of deliberation. US Defense Secretary Leon Panetta gave the news to his French counterpart, Jean-Yves Le Drian in a telephone conversation Saturday, a Pentagon spokesman said.

They also discussed plans for the Americans to transport troops from African nations, including Chad and Togo, to facilitate the international effort in Mali.

The US military has an unparalleled fleet of more than 400 tankers equipped to refuel fighters and other warplanes in mid-air. France has about 14 such tankers.

-- Slow deployment of regional forces --

French-led forces took Gao from the Al-Qaeda-linked Movement for Oneness and Jihad in West Africa (MUJAO), one of the Islamist groups that for 10 months have controlled northern Mali.

France said troops from Niger and Chad "will pick up the baton" and that the mayor of Gao, Sadou Diallo, was due to return from the capital Bamako, 1,200 kilometres (750 miles) to the southwest.

"A first contingent of Malian, Chadian and Niger troops are presently in Gao to help secure it," a Malian security source told AFP Saturday by telephone from the town. They had been flown in from Niamey, capital of neighbouring Niger.

Other soldiers from Chad and Niger meanwhile were moving toward the Malian border from the Niger town of Ouallam, which lies about 100 kilometres southeast of Gao.

Mali was expected to be top of the agenda at the African Union (AU) summit in the Ethiopian capital Addis Ababa opening Sunday.

On Saturday, West African defence chiefs meeting in Ivory Coast agreed to boost the their troop pledges for the force to 5,700 from the previous 4,500.

Chad, which neighbours Mali but is not a member of the Economic Community of West African States (ECOWAS) raising the force, has promised an additional 2,000 soldiers.

So far however, only a fraction of the African troops have arrived in Bamako, the Malian capital in the south of the country. French and Malian forces have done all the fighting to date.

The AU last week agreed to seek help from the United Nations with transport, medicine and field hospitals for the African-led force in Mali, or AFISMA.

France has already deployed 2,500 troops to Mali and its defence ministry says 1,900 African soldiers are on the ground there and in Niger.

Aid agencies have shown concern about the growing food crisis for civilians in the vast semi-arid north of Mali and the drought-stricken Sahel as a whole.

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