“The United States rejects efforts to overturn the constitutional order, and stands with the people of Niger, the Economic Community of West African States, the African Union and international partners in support of democratic governance and the respect for the rule of law and human rights,” a statement from Washington on Tuesday read.
The US said it would support sanctions against Niger imposed by Ecowas after an emergency meeting in Nigeria on Sunday.
The first evacuation flight landed in France early on Wednesday after all Niger's land and air borders were closed as part of the sanctions.
Almost 300 people, including a dozen infants, were on board the plane, French Foreign Minister Catherine Colonna said.
A second flight later arrived in Rome, while Spain has also announced it will evacuate its nationals.
The US said it is “aware” of evacuation efforts but said it had no indication of direct threats to its citizens in the country.
The Washington statement said: “The Secretary conveyed the continued unwavering support of the United States for President Bazoum and Niger’s democracy.”
The military coup led by Gen Abdourahmane Tiani has worried Western powers with troops fighting Islamist groups in Niger amid growing extremism in the Sahel region of Africa.
Gen Tiani confined President Bazoum to his residence on Wednesday and declared himself ruler two days later.
Washington has suspended counter-terrorism training in Niger following the coup but remains in “close contact” with military leaders.
It has about 1,100 troops stationed in the country and officials have said there are no immediate plans to pull them out.
In December, the EU set up a three-year military mission in Niger, sending between 50 and 100 troops on a training mission, while France has between 1,000 and 1,500 troops in the country.
Germany suspended financial aid and development co-operation, and UN humanitarian operations have been put on hold.
While the coup has been largely condemned regionally and in the West, some African nations have lent support to the military leaders, saying Ecowas sanctions are a “declaration of war.”
Guinea, Burkina Faso and Mali, all under military rule, have urged Ecowas to “come to its senses.”
Mali and Burkina Faso, which have each undergone two coups since 2020, said in a joint statement that “any military intervention against Niger will be considered a declaration of war against Burkina Faso and Mali” and denounced Ecowas economic sanctions as “illegal, illegitimate and inhumane.”
On Wednesday, more than 460 Egyptian troops that contributed to a decade-long UN peacekeeping mission in Mali left the country as the mission begins a drawdown, expected to be completed by the end of the year, the UN said on Wednesday.
Troops from Senegal, Burkina Faso, Ivory Coast and Bangladesh, some of the largest contributors to the mission, will also leave in the coming days, the UN said.