Two western African states said that they would join forces to defend Niger, where soldiers claimed to have seized power in a coup last week, if a major regional bloc carried through on a threat to intervene militarily unless the ousted president is returned to office.
The joint statement late Monday by the two states, Mali and Burkina Faso, was a stinging rebuke to the regional bloc, the Economic Community of West African States, or ECOWAS. On Sunday, the bloc vowed to take “all measures necessary,” including possible military action, to force the reinstatement of Niger’s president, Mohamed Bazoum.
Mali and Burkina Faso, themselves ruled by military governments that took power in coups, said that any move against Niger would be considered a “declaration of war” against their own countries.
The statement further raised the stakes in a spiraling crisis that has exposed deep regional fissures and set off international alarm over the direction of a region where a succession of governments have fallen to military takeovers in the past four years. It also raised the prospect that the crisis in Niger, where about 2,600 American and French troops are stationed, could spread into a wider regional conflict.
France said on Tuesday that it would begin evacuating French and European citizens from Niger immediately, citing violent attacks by coup supporters against its embassy on Sunday and the closure of Niger’s airspace.
“France’s only priority is the security of our nationals,” Catherine Colonna, the French foreign minister, said on French television on Monday.
Italy said on Tuesday it would set up a special flight to evacuate its citizens, too.
Uncertainty persists over who is truly charge in Niger, an impoverished nation of 25 million people that is twice the size of France.
Mr. Bazoum, who was detained by his own guards on Wednesday, is being held in his private residence near the presidential palace in the capital, Niamey. But he can receive visitors — a photo posted to social media on Sunday showed a smiling Mr. Bazoum sitting with the visiting president of Chad, Mahamat Déby, a mediator in the crisis — and he takes phone calls from world leaders and his own officials.
Niger’s ambassador to Britain and France, Aïchatou Boulama Kané, told the BBC on Tuesday that she had spoken to Mr. Bazoum and that he was doing well. “His morale is high,” she said. The ambassador said that she was speaking on behalf of the deposed president and not for Gen. Abdourahmane Tchiani, the junta leader who now claims to be running the country.
The crisis is a stiff test for ECOWAS and its head, the recently elected president of Nigeria, Bola Tinubu. The group had already suspended Burkina Faso, Mali and Guinea over military coups in those countries since 2020. The tough statement on Sunday signaled that the bloc was ready to move militarily if necessary, despite a checkered record of interventions in regional conflicts.
ECOWAS set a deadline of next Sunday for Mr. Bazoum’s reinstatement. For now, though, it hopes to combat the coup attempt through an economic blockade of landlocked Niger, which depends heavily on its neighbors for trade and financial stability. The measures announced on Sunday included a slate of punishing sanctions against the coup leaders, as well the suspension of all trade and financial transfers between its member states and Niger. The bloc has also frozen Niger’s assets in regional banks.
Guinea, which has been ruled by a military junta since 2021, said it would not join in sanctions against Niger, but made no mention of possible military action.
But the junta leaders have found powerful support in their fellow military leaders of Mali and Burkina Faso. Both countries have experienced two coups since 2020 and have ties of varying degrees to Russia. The junta in Mali expelled 5,000 French troops and brought in 1,500 mercenaries with Wagner, the Kremlin-backed private military company, which has since been accused of leading massacres in which hundreds of civilians were killed.
Burkina Faso has moved closer to Russia in recent months. Its leader, Capt. Ibrahim Traoré, issued abundant praise of Russia during a meeting with President Vladimir V. Putin at a Russia-Africa summit in St. Petersburg last week.
France’s evacuation from Niger, supposed to start on Tuesday, is the latest in a succession of blows to French power and prestige in western and central Africa, a region it dominated for decades after the end of colonialism in the 1960s. In recent years, France has been forced to withdraw its troops from Mali and from Burkina Faso, where they had been helping to fight a surge in Islamist militancy.
Even in countries without an insurgency, like Senegal, demonstrators have targeted symbols of French economic or political might, like diplomatic buildings or French-owned gas stations and supermarkets.
In Niger on Sunday, hundreds of protesters flung stones and Molotov cocktails over the French Embassy’s wall, Ms. Colonna said. The tumult echoed earlier attacks on the French Embassy in Burkina Faso in September after the latest coup in that country.
Niger has one of the world’s biggest reserves of uranium and is an important part of Europe’s energy system.
The biggest mines in a remote desert area in the nation’s northwest are operated by companies from France, which discovered uranium in Niger in 1957 during a colonial-era expedition to prospect for copper. Canadian, Chinese and South Korean companies, among others, also have mining stakes there now.
Interest in Niger’s uranium intensified last year as European nations looked to wean themselves from dependency on energy supplies from Russia. Niger was the second-biggest supplier of uranium to the European Union in 2022, according to Euratom, the continent’s nuclear agency.
The French energy company Orano, which has operations in Niger, said in a statement posted on its website that it had “stepped up its vigilance” to protect the safety of its employees and sites in the country.
Aurelien Breeden contributed reporting from Paris.