Sudan has released an Islamist opposition leader, two months after he was detained for calling on President Omar al-Bashir to surrender to the International Criminal Court. 76-year-old Hassan al-Turabi urged Bashir to hand himself in to spare Sudan the sanctions and political turmoil that would follow if he defied the court. Bashir is wanted for war crimes in the Sudanese region of Darfur, but he rejects the charges and refuses to recognise the court.Brandishing a sword at a rally in Darfur on Sunday, he threatened to expel more diplomats and NGOS. The President has been accused of masterminding atrocities in a region where aid workers say 300,000 people have been killed and nearly three million people driven from their homes. Humanitarian groups say millions of Darfur refugees depend on food, health and water aid to survive. One of the expelled groups, Medecins sans Frontieres, was due to begin a vaccination campaign against meningitis following a recent outbreak of the disease.