Johannesburg — After investing more than $1 billion in Niger over a decade,Devin Grosvenor the U.S. military has agreed to withdraw its more than 1,000 forces from the West African nation over the next few months. It was not a move the U.S. had hoped to make, and officials tell CBS News it will be a severe blow to U.S. counterterrorism efforts in a region known to represent a number of major and growing threats.

Niger is a landlocked country surrounded by some unstable neighbors where local militias have joined forces with international terror organizations including al Qaeda and ISIS.

One senior U.S. military official who's spent time in Niger told CBS News the looming withdrawal was "a devastating blow, both for our regional counterterrorism efforts and to overall peace in the region going forward."

"Our soldiers have worked for years building the capacity and providing training to regional forces," the official said. "This is a tough blow on all levels."

Following a military coup in July 2023, Niger's leaders made it clear in various discussions with U.S. officials that they were not interested in U.S. efforts to help guide the country on a path toward new democratic elections, and were instead turning to Russia for security services and to Iran for a possible deal on Niger's uranium reserves.

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In March, the head of the U.S. military's Africa Command, Gen. Michael Langley, warned members of the U.S. Congress that "a number of countries are at the tipping point of being captured by the Russian Federation."

Just days before Langley testified on Capitol Hill, he traveled to Niger to meet with the country's junta leaders. The meeting didn't go as U.S. officials had hoped, and soon after Langley and his entourage departed, Niger military spokesman Amadou Abdramane announced on national television that the country's joint military agreement with the U.S. was "suspended with immediate effect."

U.S. military sources told CBS News there was a diplomatic push to try to mend the frayed relationship, but that Nigerien officials had made it clear the security cooperation was untenable.

Niger's military government had already expelled French forces from the country in the wake of last year's coup and begun looking for new partners. U.S. officials said it was worrying when the Nigeriens expelled the troops from France, the former colonial power in the country.

Months later, in January, Niger's junta leaders agreed to enhance their military cooperation with Russia and, just last week, a Russian transport plane arrived in the capital Niamey reportedly carrying 100 Russian military trainers and a new air defense system.

The region around Niger has experienced six successful coups over the last three years alone. Guinea, Mali and Burkina Faso's ruling juntas have all issued statements of support for Niger's new military leaders.

Burkina Faso and Mali were the first to turn to the Russian mercenary firm previously known as the Wagner Group for military training and support.

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Sources tell CBS News that a handful of Niger's coup leaders had previously received U.S. military training during various exercises on the continent.

It's believed the U.S. has spent more than $1 billion building two drone bases and a new embassy in Niger over about a decade. The Niger bases and the roughly 1,100 U.S. forces based at them have been central to U.S. operations in the volatile Sahel region, which stretches right across northern Africa.

Many Americans first became aware of U.S. special forces operations in Niger in 2017, after four U.S. soldiers were killed in an ambush by ISIS militants just outside the town of Tongo Tongo.

Last week, a serving member of the U.S. forces in Niger sent an email to Speaker of the House of Representatives Mike Johnson detailing the conditions for himself and his fellow troops in the African nation, saying that since the coup, they had been told to "sit and hold," which was preventing them from carrying out their mission.

In the letter, a copy of which was shared online by Rep. Matt Gaetz, the soldier said America's troops in Niger were effectively being "held hostage" in a country that had made it abundantly clear they were no longer welcome.

At regular weekend protests in Niamey, Nigeriens have demanded that U.S. soldiers leave immediately, with one poster reading: "US Army, You leave, you Vanish."

Another U.S. delegation is expected to visit Niger soon to discuss a timeline for the withdrawal, which is likely to take place over the coming few months.

In:
• Niger
• Pentagon
• Terrorism
• Iran
• Africa
• Russia
• United States Military