The African Union says it has suspended Guinea Bissau's membership of the organisation after a coup last week by the west African state's military.At a meeting in the Ethiopian capital Addis Ababa, the AU's Peace and Security Council decided to suspend Guinea Bissau "until the restoration of constitutional order".The suspension takes immediate effect.The AU also says it will ask for international sanctions to be imposed on the country.Soldiers toppled the government last Thursday over its alleged plans to reduce the size of the army.The West African regional bloc, Ecowas, says the soldiers have agreed to return the country to civilian rule.The president of the Ecowas commission, Kadre Desire Ouedraogo - who has been in Bissau for talks with the coup leaders - did not say when constitutional order would be restored.There has been no word from the military.Mr Ouedraogo said he had asked for political prisoners to be released, including Prime Minister Carlos Gomes Junior, who was arrested during last week's coup.He is 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 president has completed a term since independence from Portugal in 1974.Interim President Raimundo Pereira has also been detained.Trade unions have called for a general strike in protest at the coup.The junta say they acted to prevent foreign intervention and a plot to "wipe out" Guinea-Bissau's army.About 200 Angolan officers have been in the country for the last year to help with training and reforms to the bloated army, which has long meddled in politics and is said by Western intelligence agencies to play a key part in trafficking drugs.Guinea-Bissau is a major staging post for gangs smuggling cocaine from Latin America to Europe.