The military leaders revoked the deal between Niger and the US with “immediate effect,” and is seen as ending the US presence in the sub-Saharan country. The decision is a setback to Washington, which had been forced to suspend operations at Air Base 201 in Agadez following a July coup and was pushing to keep its most strategic military asset in the region afloat.

“The American presence on Niger’s territory is illegal and violates all constitutional rules,” Amadou Abdramane, spokesman for the National Council for the Protection of the Homeland — or CNSP according to its French acronym, said in a statement on state TV and Facebook on Saturday. The US has about 1,000 troops in Niger as part of an effort to battle Islamist insurgency in West Africa’s Sahel region and Libya.

The move came after senior US officials accused the junta of secretly exploring a deal to allow Iran access to its uranium mines, the Wall Street Journal reported on Sunday, citing officials from Niger and the US it didn’t identify. The concerns were raised by Assistant Secretary of State for African Affairs Molly Phee, who was leading a three-day visit by a US delegation to Niamey over the past week, the newspaper said.

“Niger’s ending of the military cooperation with the US ends all hopes for the West to save the relationship with the new military rulers,” said Ulf Laessing, the Bamako-based head of the Sahel program at the Konrad Adenauer Stiftung. “It’s an entry card for the Africa Corps which has already put out feelers. Russia signed a military agreement in December with the junta.”

A US military official said Saturday that they were “aware of the CNSP’s Facebook post, which follows frank discussions at senior levels in Niamey this week about our concerns with the CNSP’s trajectory. We are in touch with the CNSP and will provide further updates as warranted.”

The US was the last larger Western contingent left in Niger after the junta severed military ties with France and its European partners last year. US operations were also suspended after the State Department labeled as a coup the July military takeover and ouster of President Mohamed Bazoum.

“This shows that the US strategy to stay and try to maintain relations with the military leadership, while trying to convince them to hand over power, has failed,” said Seidik Abba, who heads the CIRES think tank focusing on the Sahel region. “The US’s main concern was to prevent Russia from gaining a foothold in Niger — we know that Russia is already present in Mali and we’re hearing they recently deployed in Burkina Faso.”

Russian Troops Begin Burkina Faso Deployment to Bolster Security