French aircraft have pounded Islamist rebels in Mali for a second day, killing up to 100 rebel fighters, according to a senior army officer in the capital Bamako.

Neighbouring west African states are planning to deploy troops in an international campaign to prevent groups linked to al-Qaeda expanding their power base.

France has warned that the control of northern Mali by the militants poses a security threat to Europe.

Under cover from French fighter planes and attack helicopters, Malian troops routed a rebel convoy and drove the Islamists out of the strategic central town of Konna.

Earlier, Mali's insurgent group Ansar Dine warned that France's military intervention against Islamist fighters in northern Mali puts French hostages and other French citizens at risk.

Ansar Dine, whose stronghold is the historic city of Timbuktu, is a close ally of al-Qaeda's North African wing AQIM, which is also fighting Malian forces backed by French air power.

AQIM and its allies are holding eight French nationals in the sparsely populated Sahel region following a series of kidnappings.

Spokesperson for Ansar Dine Sanda Ould Boumama said: "There are consequences, not only for French hostages, but also for all French citizens wherever they find themselves in the Muslim world.

"We are going to continue resisting and defend ourselves. We are ready to die fighting."

A spokesman for AQIM earlier urged France, in a video posted on the internet, to reconsider its intervention.

"Stop your assault against us or you are digging your own sons' graves," said Abdallah Al-Chinguetti.

The French Foreign Ministry on Friday advised the 6,000 French citizens living in Mali to leave the country.

Government forces in Mali say they have regained territory from Islamist militants following air strikes by French military aircraft.

The development came after France announced it had begun military operations in support of the government in its former colony in west Africa.

President Francois Hollande said it had done so because Mali's very existence as a state was under threat.

Armed groups, some linked to Al-Qaeda, took control of northern Mali in April.