Mali's junta leader on Tuesday removed leaders chosen to steer the country back to civilian rule, as former colonial power France warned it could lead a charge to impose sanctions on the regime.
Col Assimi Goita, who led Mali's coup less than 10 months ago, said transitional president Bah Ndaw and prime minister Moctar Ouane had been stripped of their powers.
Col Goita also promised elections in 2022.
The detention of the pair, which was likened by French President Emmanuel Macron to a second coup, was the latest crisis to hit a state burdened with poverty and a brutal insurgency.
Mr Ndaw and Mr Ouane have been leading an interim government that was installed in September under the threat of regional sanctions, with the declared aim of restoring full civilian rule within 18 months.
But in a move that sparked widespread anger, they were detained on Monday by army officers who were unhappy with a government reshuffle.
Col Goita announced on public television that Mr Ndaw and Mr Ouane had been stripped of their duties for seeking to "sabotage" the transition, which would "proceed as normal".
In Monday's government reshuffle the military kept the portfolios it held in the previous administration.
But two other coup leaders, former defence minister Sadio Camara and former security minister Col Modibo Kone, were replaced.
Col Goita, who holds the rank of Vice President in the transitional government, accused Mr Ndaw and Mr Ouane of failing to consult him on the reshuffle.
"This kind of step testifies to the clear desire of the transitional president and prime minister to seek to breach the transitional charter," he said.
The transitional charter, a document largely drawn up by the colonels, sets down principles for Mali's return to civilian rule.
Mr Macron, whose country has committed more than 5,000 troops in the fight against extremists in the Sahel, condemned the arrests of Mr Ndaw and Mr Ouane as a "coup d'etat in an unacceptable coup d'etat".
"We are ready in the coming hours to take targeted sanctions" against those responsible, he said after an EU summit.
French Foreign Minister Jean-Yves Le Drian told Parliament in Paris that France had called for an urgent meeting of the UN Security Council to discuss the crisis.
On Monday, the UN, African Union, Economic Community of West African States (Ecowas), EU and US issued a joint statement attacking the detention and demanding the pair be released.
That demand was echoed on Tuesday by Britain and Germany.
A senior Malian military official said Mr Ndaw and Mr Ouane were taken to the Kati military camp near Bamako and "are fine".
"They spent the night in good conditions," he said. "The president saw his doctor."
A veteran Ecowas mediator in Mali's long-running crisis, former Nigerian president Goodluck Jonathan, arrived in the capital Bamako in mid-afternoon.
Young military officers removed president Ibrahim Boubacar Keita from power on August 18 after weeks of protests over perceived government corruption and his handling of the insurgency.
Ecowas, a 15-nation regional bloc, threatened to impose sanctions, prompting the junta to hand over power to a caretaker government that pledged to reform the constitution.
But many doubt whether the military-dominated government has the will or the ability to introduce reforms in such a short time.
"What we are experiencing today is the logical outcome of the flaws at the start of the transition," said sociologist Brema Ely Dicko, referring to the lack of civilian representation in the transitional government.
Monday's reshuffle came amid signs of discontent among the public, which initially praised the army for bringing down Mr Keita.
The opposition M5 movement pushed for the interim government to be dissolved, demanding a "more legitimate" body.
On May 14, the government said it would appoint a new "broad-based" Cabinet.
In the streets of Bamako, life seemed to continue as normal on Tuesday despite the removal of Mr Ndaw and Mr Ouane.
and many people interviewed by AFP said they were resigned to events.
Tahirou Bah, an activist, attacked "putschist colonels" who fought to the death for power when "80 per cent of our country is under the control of terrorists, drug traffickers and bandits of every kind".
But Mr Bah said many people simply focused on day-to-day living.
"This is survival for many Malians," he told AFP.
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