BAMAKO, Mali - French President Emmanuel Macron arrived in Mali on Sunday to boost Western backing for a regional anti-jihadist force, with France urging greater support for the Sahel region amid mounting insecurity.

The so-called "G5 Sahel" countries south of the Sahara - Burkina Faso, Chad, Mali, Mauritania and Niger - have pledged to fight jihadists on their own soil with instability and Islamist attacks on the rise.

Macron is joining these nations' heads of state in Bamako for a special summit where France's backing for the force will be announced, with a likely focus on providing equipment.

Based in Sevare, central Mali, the 5,000-strong G5 Sahel force aims to bolster 12,000 UN peacekeepers and France's own 4,000-member Operation Barkhane, which is deployed in the region.

"Every day we must combat terrorists, thugs, murderers ... who we must steadfastly and with determination eradicate together," said Macron.

Macron is also looking to extra backing from Germany, the Netherlands, Belgium and the United States - which already has a drone base in Niger - beyond a pledge of $57.2 million made by the European Union.

Serge Michailof, a researcher at the Paris-based IRIS institute, described the EU contribution as "a joke" given the EU's "very deep pockets" and the poverty of the Sahel countries.

"This force is going to cost $300-400 million at the very least," he said.

Chadian President Idriss Deby has said his country cannot afford to mobilize large numbers of troops simultaneously for the UN peacekeeping mission and also in the new force.

Deby and Macron are due to meet on the margins of the Bamako summit to discuss the financial issue, according to the French presidency. Chad's military is widely viewed as the strongest of the Sahel nations.

The visit comes as al-Qaida's Mali branch offered a reminder of the jihadists' threat, with the release of a proof-of-life video of six foreign hostages.

The clip posted on Saturday by Nusrat al-Islam wal Muslimeen, also known as the Group to Support Islam and Muslims, includes elderly Australian surgeon Arthur Kenneth Elliott and Frenchwoman Sophie Petronin.

Elliott was abducted in January 2015 in Djibo, Burkina Faso, where he and his wife had run the district's sole medical clinic since 1972. Petronin was abducted in late 2016 in the northern Malian town of Gao.

In the video, the hostages are separately introduced by a narrator, who says that so far there have been no negotiations for their release.

Macron visited Gao in northern Mali in May, his first foreign visit as president outside Europe, and promised French troops would remain "until the day there is no more Islamic terrorism in the region".

France intervened to chase out jihadists linked to al-Qaida who had overtaken key northern cities in Mali in 2013.

Agence France-presse