The United States has ordered the partial evacuation of its embassy in Niger following last week’s coup.
Hundreds of foreign nationals have already been evacuated from the country, and on Sunday the French embassy was attacked by protesters.
Coup leader Gen Abdourahamane Tchiani has warned against “any interference in the internal affairs” of the country.
Niger is a significant uranium producer and lies on a key migration route to North Africa and the Mediterranean.
US state department spokesperson Matthew Miller said that, despite the partial evacuation, the country’s embassy in the capital Niamey would remain open.
“We remain committed to the people of Niger and our relationship with the people of Niger and we remain diplomatically engaged at the highest levels,” he said.
The US is a major donor of humanitarian and security aid to Niger, and has previously warned that the coup could lead to the suspension of all co-operation.
France, the former colonial power in Niger, and the EU have already suspended financial and development aid.
A West African trade bloc, the Economic Community of West African States, has imposed sanctions which include a halt on all commercial transactions with Niger and a freeze on the country’s assets in the regional central bank.
The bloc is also considering a military intervention.
In a televised address on Wednesday, Gen Tchiani said the new regime rejected “these sanctions as a whole and refuses to give in to any threat, wherever it comes from”.
He labelled the sanctions “cynical and iniquitous” and said they were intended to “humiliate” Niger’s security forces and make the country “ungovernable”.