UN Secretary General Antonio Guterres has told RFI Mali could collapse if the UN withdraws its peacekeeping mission there, but suggested an option could be to replace it with an African Union force backed by a tougher operating mandate.
The UN Security Council will decide next month whether to renew the mandate of its peacekeeping mission in Mali (Minusma).
"The true situation is that without Minusma, the risk of the country's collapse would be enormous," Guterres said in an interview with RFI as he concluded a three-nation tour of West Africa.
"I am not going to propose that this mission be ended because I think that the consequences would be terrible.
"But it is operating in circumstances that really call not for a peacekeeping force, but a strong force to enforce peace and fight terrorism."
Guterres said the force would need to be African, and "from the African Union, but with a Chapter Seven Security Council mandate and obligatory financing" – referring to a UN charter that permits the use of armed force in the event of a "threat to peace”.
Minusma, which deploys 14,000 troops and police, is one of the UN's largest peacekeeping forces. It was created in 2013 to help support Mali fight against jihadist insurgents.
But the force has often been criticised for being shackled by a mandate that has left it unable to make robust interventions, putting the security onus on Mali's poorly equipped armed forces.
Most of the contingents in Minusma are supplied by African countries and it has lost 170 members since 2013, many of them killed by roadside bombs or in ambushes.
"It really is a very difficult ... situation for us," Guterres acknowledged.
He highlighted the "very difficult cooperation" between Mali and Minusma on the question of human rights.
Last month, several hundred civilians were killed in central Mali by government forces and foreign operatives, believed to be from the Russian Wagner group.
Mali denies this, and says its forces eliminated more than 200 jihadists.
The UN says it is still awaiting permission from the authorities to send investigators to the region.
More help for Niger
Next month's decision in New York comes at a time of worsening relations between Mali and France, which pulled its Barkhane troops out of the Sahel state in February and has moved many to its bases in Niger.
Niger is also battling a jihadist insurgency and on Tuesday, Guterres met displaced people and refugees in Ouallam, Niger, as part of his three-nation tour.
He urged the international community to invest in Niger, notably by funding equipment and training for its army.
“The presence of Barkhane or [European military task force] Takuba is extremely important,” Guterres said, adding “my experience tells me that it is not possible to defend a country only with foreign troops.
“We have to reinforce the country's capacity to defend itself."
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Niger's army had shown “remarkable courage” despite being poorly equipped, he said, stressing the need for it to be able to move around more quickly with better intelligence, drones, air-conditioned vehicles and night-vision equipment.
“When you see the situation in Burkina Faso, in Mali, where there are military coups, I believe we must really transform the border with Niger into a wall to block terrorism. And to do that, Niger's needs to a much better capacity than it has today."
Several Western countries already support Niger, notably France and the United States, which have military bases in the capital, Niamey, and the Agadez region in the north.
On Sunday in Dakar, Guterres called for the military juntas that have taken power in Burkina Faso, Guinea and Mali to hand power back to civilians as soon as possible.
The three countries have been suspended by Ecowas, which has also urged the juntas to return the countries to democratic rule as soon as possible.