Niger's new military ruler General Abdourahamane Tiani has said a transition of power would not go beyond three years, and warned that any attack on the country would not be easy for those involved.

"Our ambition is not to confiscate power," General Abdourahamane Tiani said in a televised address on Saturday, adding that an attack on Niger would not be "a walk in the park".

He also said: "ECOWAS is getting ready to attack Niger by setting up an occupying army in collaboration with a foreign army," without saying which country he meant.

In his 12-minute speech, Tiani denounced what he called the "illegal" and "inhuman" sanctions levied by ECOWAS against Niger since the military seized power.

He also announced a 30-day period of "national dialogue" to draw up "concrete proposals" to lay the foundations of "a new constitutional life".

His warning came as a delegation from West African bloc ECOWAS arrived in the country for a final diplomatic push before deciding on whether to take military action.

Representatives from the West African regional bloc, ECOWAS, led by former Nigerian head of state General Abdulsalami Abubakar, met separately with Tiani, the junta leader, and toppled President Mohamed Bazoum.

They joined efforts by the United Nations Special Representative for West Africa and the Sahel, Leonardo Santos Simao, who arrived on Friday, in trying to facilitate a resolution to the predicament.