PARIS (Reuters) - International donors have disbursed less than half of what they had pledged for a regional force fighting to contain West African jihadists, hampering its efforts as insecurity spreads across the region, a United Nations report said.

FILE PHOTO: United Nations Secretary-General Antonio Guterres gives a statement after delivering a speech on disarmament and denuclearisation at the University of Geneva (UNIGE) in Geneva, Switzerland, May 24, 2018. REUTERS/Denis Balibouse/File Photo

A February conference of about 50 countries including the United States, Japan and Norway pledged 415 million euros ($470 million) for the G5 Sahel force, made up of troops from Mali, Niger, Chad, Burkina Faso and Mauritania.

But the force has struggled to get off the ground and in his Nov. 12 report to the Security Council, U.N. Secretary General Antonio Guterres said only 45.9 per cent of funds (about 190.76 million euros) had either been disbursed or allocated for procurement processes.

“The support measures and the funding mechanism put in place must be revisited,” Guterres said.

The G5 force has been hobbled by delays and poor coordination between the five countries, officials and diplomats say, while insecurity has escalated in the border region between Mali, Niger and Burkina Faso.

Three civilians were killed on Monday after a car bomb exploded in the northern Malian city of Gao, an attack claimed by an Islamist militants.

“The spread of insecurity and terrorism to other parts of the region, including into eastern Burkina Faso, is particularly worrying,” Guterres said. “Rebel attacks in eastern Chad indicate that borders are becoming more porous.”

The arid Sahel region has been fertile ground for groups linked to al Qaeda and Islamic State, highlighting difficulties international partners face in restoring regional stability.

France, the former colonial power in the region, intervened in Mali in 2013 to drive out Islamist militants occupying the north and has since kept about 4,500 troops in the region as part of counter-terrorism operations. The U.N. has thousands of troops in Mali as part of its peacekeeping mission.

Paris pushed the G5 force creation with the long-term aim of placing the region’s security in the hands of local forces.