"Any military intervention against Niger would be tantamount to a declaration of war against Burkina Faso and Mali," they warned, adding that such a move could result in "disastrous consequences" that "could destabilise the entire region".
In a dangerous turn of events, military-ruled Burkina Faso, Mali, and Guinea have declared their support for the coup in Niger.
Burkina Faso and Mali in a joint statement on Monday warned that any military intervention against Niamey would be considered a declaration of war against their nations.
"Any military intervention against Niger would be tantamount to a declaration of war against Burkina Faso and Mali," they warned, adding that such a move could result in "disastrous consequences" that "could destabilise the entire region".
The warning was read out on their national broadcasters a day after ECOWAS threatened to use force to reinstate Niger's deposed President Mohamed Bazoum should the coup plotters not comply after seven days.
"The transitional governments of Burkina Faso and Mali express their fraternal solidarity... to the people of Niger, who have decided with full responsibility to take their destiny in hand and assume the fullness of their sovereignty before history," Aljazeera quoted the two countries as saying.
They described sanctions imposed on Niger as "illegal, illegitimate and inhumane against the people and authorities of Niger hence will not apply them."
In Guinea, a post made on the social networking platform X said "the National Committee of the Rally for Development (CNRD) firmly expressed its support for the people of this friendly country (Niger), emphasising the importance of the values of Pan-Africanism dear to the Head of State, Colonel Mamadi Doumbouya."
It dissociated itself from the sanctions imposed by ECOWAS.
Niger's coup leaders named General Abdourahamane Tchiani, the former presidential guard chief, as head of state, saying they overthrew President Mohamed Bazoum due to poor governance and discontent with the way he handled security threats from groups linked to al-Qaeda and ISIS (ISIL).
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While countries declare support for the coup plotters, Niger's military are arresting top officials of the toppled government.
The mines minister, oil minister and head of the ruling party were among those arrested on Monday, according to the PNDS party.
The party also noted that the interior minister, transport minister and a former defence minister, have also been arrested.
