A national conference in Burkina Faso has adopted a charter that will allow a junta that seized power in the West African state in January to lead a 3-year transition, a Reuters reporter said.

The conference approved the charter, which was later signed by junta leader Lt. Colonel Henri-Paul Damiba in the early hours of Tuesday after a day-long debate in the capital Ouagadougou.

Damiba, who did not speak during the signing, led the January 24 coup that ousted President Roch Marc Kabore.

The coup, the fourth in the West Africa region in 18 months, including two in Mali, and an attempted coup in Guinea Bissau in early February, have raised concerns of a backslide in democracy in a region that was shedding its 'coup belt' moniker.

A commission that drafted the transitional charter had proposed a two-and-a-half year transition, saying the junta had said it needed around two years to stabilise the country and organise elections.

Burkina Faso, alongside neighbours Mali and Niger, is struggling to contain attacks by armed militants linked to al Qaeda and Islamic State who have killed thousands of people and displaced hundreds of thousands in the West Africa Sahel area, rendering swathes of territories ungovernable and weakening governments.

Eddie Komboigo, leader of a main opposition party who came second in the 2020 presidential election, welcomed the charter.

"It is true that not everyone is going to be happy with the transitional charter... but is was the consensus that we reached," Komboigo said, urging the junta to negotiate with regional leaders and international partners so that all can agree on the length of the transition.

Burkina Faso was suspended from the Economic Community of West African States, and the African Union, which have both called for a speedy return to constitutional order, while the US has halted nearly $160-million aid due to the coup.