Guinea-Bissau's military junta has said it will hold elections in two years following the coup last week.
Correspondents say the time frame is unlikely to appease the international community and regional mediators.
The coup-prone West African nation has already been suspended from membership of the African Union until constitutional order is restored.
Meanwhile, the World Bank and the African Development Bank have suspended their development programmes.
The two lenders say emergency assistance will continue and are urging "a speedy resolution of the crisis".
Guinea-Bissau, which has a long history of military take-overs since independence from Portugal in 1974, is one of the world's poorest countries - with almost 70% of people living in poverty and it is heavily dependent on foreign assistance.
Earlier this week, mediators from the West African regional bloc, Ecowas, held talks with the soldiers and said they had agreed to return the country to civilian rule, but no time frame was given.
The organisation recently intervened in Mali, imposing sanctions which forced the coup leaders - within weeks of last month's putsch - to hand over power to an interim president who must organise elections within 40 days.
Wednesday's accord in Guinea-Bissau outlining the transition period was signed with some opposition parties - but not with the country's PAIGC party, which has dominated politics since independence.
It confirms the dissolution of parliament and the creation of a National Transitional Council which will name an interim president and government.
Soldiers say they toppled the government over its alleged plans to reduce the size of the army.
The country's leaders, interim President Raimundo Pereira and Prime Minister Carlos Gomes Junior, were arrested during last week's coup.
Mr Gomes was the only candidate in the second round of presidential elections scheduled for 29 April, called after the death in January of President Malam Bacai Sanha following a long illness.
Opposition candidate Kumba Yala pulled out of the poll, claiming fraud.
No elected leader in nearly 40 years of independence has finished their time in office in Guinea-Bissau, which has now become a major staging post for gangs smuggling cocaine from Latin America to Europe.