Gen Mohamed Ould Abdelaziz launched the coup after he was sacked
Mauritania's military leaders have promised to hold elections by June this year, local media report.
The prime minister said polls would take place within six months, according to state radio.
The independent Al-Akhbar news agency quotes official sources as saying that elections would be held at the same time as a constitutional referendum.
The army seized power last August, toppling Mauritania's first democratically elected leader.
There has been intense international pressure on the coup leaders to return the country to democracy.
Sidi Mohamed Ould Cheikh Abdallahi became Mauritania's first democratically elected leader in 2007 after a coup two years earlier.
Mr Abdallahi was under house arrest until last month.
He was ousted after trying to dismiss four senior army officers, including Gen Mohamed Ould Abdelaziz, the head of the presidential guard, who responded by launching the coup.
Mauritania has a long history of coups, with the military involved in nearly every government since its independence from France in 1960.