Soldiers in Mali have seized control of the west African country at the heart of the fight against jihadism in the Sahel in the second coup in less than a year.

Late on Monday, the military officer behind an August coup ordered the arrest of the president and prime minister. Colonel Assimi Goita, who has served as interim vice-president since the junta he led putatively handed power to a transitional government in September, said he had ordered the arrest because the officials had not consulted him on a cabinet reshuffle that excluded key junta members.

“The vice-president of the transition saw himself obligated to act to preserve the transitional charter and defend the republic,” an aide said in a statement read on national TV. In the statement, Goita promised that elections planned for February would still go ahead.

President Bah N’Daw and Prime Minister Moctar Ouane were still in detention on Tuesday.

The UN, African Union, France and the US called for the immediate release of the officials in a joint statement that called the arrests an “attempted coup”.

“The reckless action carried out today carries with it the risk of weakening the mobilisation of the international community in favour of Mali,” the group said.

The Economic Community of West African States, the regional bloc that was due to send a delegation on Tuesday, also condemned the arrests. The US state department called for their “immediate, unconditional release”.

Mali depends largely on international support for what little stability it has: a 13,000-troop UN peacekeeping force, thousands of trainers and aid workers from the EU, international NGOs and other allies, and roughly 5,000 French counterterror troops who cover the entire Sahel.

Instability in the country has grown since France intervened to crush a jihadist insurgency that captured northern Mali in 2013, with violence spreading to neighbouring Niger and Burkina Faso. The conflict, along with widespread perceptions of corruption and neglect, led to weeks of mass protests against then president Ibrahim Boubacar Keita last year, which culminated in a coup on August 18.

The mid-level military officers who led the coup agreed, after international and domestic pressure, to set up a transitional government that would return the country to civilian rule within 18 months.

But fears of persistent military influence were confirmed when coup leader Goita was appointed vice-president, and the rest of the cabinet was filled out with other members of the junta.

N’Daw is a former colonel and defence minister who had served under Keita and as an aide to former dictator Moussa Traoré. His arrest came just hours after a new cabinet was announced that did not include defence minister Sadio Camara or interior security minister Modibo Kone, both key junta supporters.