The United States on Monday urged Guinea's coup leader to set a timeline for new elections after he was sworn in as interim president.

Colonel Mamady Doumbouya said he was committed to a transition to civilian rule, but was sworn in Friday to lead the West African nation for a transition period of unspecified length.

"The United States urges Guinea's military junta to appoint a civilian head of the transitional government and commit to a timeline for free and fair elections to return the country to civilian rule, democracy and constitutional order," a State Department spokesperson said.

The spokesperson said that civilians including opposition leaders, women and marginalized groups needed to have a "central role" in the transition.

The military on September 5 ousted Alpha Conde, who became the turbulent nation's first democratically elected president in 2010 but last year pushed through a controversial new constitution that allowed him to seek a third term, setting off deadly protests.

The region's bloc, the Economic Community of West African States (ECOWAS), is demanding that elections be held within six months and that Conde be released.