African powers launched a new multinational military force to tackle Islamist militants in the Sahel today, which French President Emmanuel Macron told a regional summit should be fully operational by the autumn.

Some observers see the initiative of the G5 Sahel bloc - Mali, Mauritania, Burkina Faso, Niger and Chad - as forming the basis of an eventual exit strategy for around 4,000 French troops now deployed to the volatile region. But Mr Macron said Paris had no plans to withdraw them.

Islamist militant groups, some with links to al-Qaeda, seized control of Mali's desert north in 2012.

Though they were driven back a year later by a French-led military intervention, they continue to carry out attacks on UN peacekeepers, Malian soldiers and civilian targets in violence that has spilled across Mali's borders.

"Every day we must combat terrorists, thugs, murderers, whose names and faces we must forget, but whom we must steadfastly and with determination eradicate together," Mr Macron said at the summit in Mali's capital Bamako.

During the meeting, leaders of the G5 Sahel countries formally established the new force, which will operate in coordination with French troops and MINUSMA, Mali's struggling UN peacekeeping mission.

The countries of the G5 Sahel bloc began floating the idea of a regional force as early as 2015, but since taking office in May, Mr Macron has thrown Paris's weight behind the plan, including through a UN resolution last month.

"There is urgency because those we're confronting are not going to wait," said Mali's President Ibrahim Boubacar Keita. "It's also clear that France alone must not continue to bear the burden of this fight against terrorism."

Mr Macron said the force, which is expected to consist of around 5,000 troops, needed to be fully operational by this autumn.

But he played down speculation that he was seeking to reduce the burden on France's cross-border Barkhane Operation, saying in a meeting with Mali's French community following the summit that Paris would "remain engaged for as long as it takes".

Paris considers the Sahel area a breeding ground for militants and traffickers who pose a threat to Europe.

Late yesterday, JNIM, an al-Qaeda-linked group, released a video showing six Western hostages abducted in the region in recent years.

Among them was French citizen Sophie Ptronin, Mr Macron said France would "put all our energy towards eradicating" the kidnappers.