West African leaders will hold a summit on the crisis in Niger this week after the country's military rulers defied an ultimatum to restore the elected government or face possible military intervention.
In its first official reaction since Niger ignored the deadline of midnight on Sunday to reinstate democratically elected President Mohamed Bazoum, the Economic Community of West African States said it would meet in the Nigerian capital Abuja on Thursday.
"The Ecowas leaders will be considering and discussing the political situation and recent developments in Niger during the summit," the 15-nation bloc said on Monday.
Ecowas had issued its ultimatum at a previous summit in Abuja on July 30, warning it did not rule out the "use of force" in Niger.
No foreign troops were visible on the streets of Niger's capital, Niamey, after the deadline came and went on Sunday.
On Sunday, as the Ecowas deadline expired, the junta closed its airspace until further notice.
"Niger's armed forces and all our defence and security forces, backed by the unfailing support of our people, are ready to defend the integrity of our territory," a junta representative said in a statement on national TV.
Landlocked Niger is more than twice the size of France and many flight paths across Africa would normally pass through its airspace.
Air France suspended flights to and from Ouagadougou in Burkina Faso and Bamako in Mali, which both border Niger, until Friday and warned some flight times would increase.
An escalation in Niger's stand-off with Ecowas would further destabilise one of the world's poorest regions, which is in the grip of a hunger crisis and battling an Islamist insurgency that has killed thousands and forced millions to flee.
Niger's uranium and oil reserves and its pivotal role in a war with Islamist insurgents in the Sahel give it economic and strategic importance for the United States, Europe, China and Russia.
Ecowas defence chiefs agreed on a possible military action plan if the detained president, Mohamed Bazoum, is not released and reinstated, although they said the operational decisions of when and where to strike would be decided by heads of state.
Regional unity is compromised by a promise from the ruling juntas in Mali and Burkina Faso to come to Niger's defence if needed. Both countries were sending delegations to Niamey to show solidarity, the Malian army said on social media on Monday.
Flight tracking website Flightradar24 showed that a Burkina Faso military plane arrived in Niamey from Ouagadougou at about 1120 GMT.
Hope for diplomacy
African and Western allies have imposed sanctions and cut aid to Niger in attempts to pressure the junta to step down. Germany on Monday said sanctions were on the table and described the junta's flight ban as a setback.
Italian Foreign Minister Antonio Tajani, however, said in an interview published on Monday that Ecowas should extend its deadline for the reinstatement of Mr Bazoum.
"The only way is the diplomatic one," Mr Tajani told La Stampa newspaper.
"It is right that he [Bazoum] should be freed but we cannot do it. The United States are very cautious about this, it is unthinkable that they would start a military intervention in Niger."
Italy on Sunday said it had reduced its troop numbers in Niger to make room in its military base for Italian civilians who may need protection if security deteriorates.
France has warned its citizens against all travel to Niger, while the Chinese embassy in Niamey said its citizens in Niger should leave for a third country or return home if they had no reason to stay.
UN Secretary-General Antonio Guterres expressed concern over the continued detention of President Bazoum and the failure to restore constitutional order in Niger, reiterating his full support to ECOWAS’ mediation efforts.
Mr Bazoum said in an opinion piece published last week that he was a hostage and called on the US and the international community to restore constitutional order.
US Secretary of State Antony Blinken on Friday called for "the immediate restoration of Niger's democratically elected government" and said the US would pause certain foreign assistance programmes that benefit the government of Niger.
"There is a rather extraordinary alignment of the West and of Africa ... to condemn what is happening," French European Affairs Minister Laurence Boone said on Monday.
"I hope we will be able to restore democracy and the constitution without blood and in peace," Ms Boone said on French TV channel LCI.