Soldiers claim to have overthrown Niger's government following an apparent coup in the West African nation during which members of the Presidential Guard detained President Mohamed Bazoum.

Members of the elite guard sealed off access to the president's residence and offices in the capital Niamey, and after talks broke down, "refused to release" him, a presidential source said.

The soldiers said "all institutions" in the country would be suspended, borders were closed and a curfew imposed "until further notice" from 10pm to 5am.

"We, the defence and security forces... have decided to put an end to the regime" of President Bazoum, Colonel-Major Amadou Abdramane said in a televised address late on Wednesday.

"This follows the continued deterioration of the security situation, poor economic and social governance," he added, surrounded by nine other uniformed soldiers.

Regional and global leaders have called for the release of Bazoum, who entered office two years ago in Niger's first peaceful transition of power since independence from France in 1960.

The president of neighbouring Benin, Patrice Talon, will head to Niamey for mediation efforts, the head of the Economic Community of West African States said.

One of a dwindling group of pro-Western leaders in the Sahel, Bazoum was elected in April 2021, taking the helm of a country burdened by poverty and jihadist insurgencies.

In a message on Twitter, which is being rebranded as X, the president's office said "elements of the Presidential Guard had a fit of temper... [and] tried unsuccessfully to gain the support of the national armed forces and the national guard".

Hours after his detention, Bazoum's supporters had tried to approach the official complex, but were dispersed by members of the Presidential Guard who fired warning shots, according to a reporter from the AFP news agency.

The parties of Niger's ruling coalition in Niamey denounced "a suicidal and anti-republican madness" in a statement, saying that "certain elements of the presidential guard sequestered the President" and his family, as well as the interior minister. (AFP)