The U.S. and Russia have agreed on the conditions of a cease-fire in Syria, U.S. officials announced Monday. The truce, poised to start Saturday, will exclude attacks on the Islamic State group and on al Qaeda affiliate Nusra Front. Russia first got involved in the civil war in September when it launched air strikes against rebels fighting Syrian President Bashar al-Assad.
More than a quarter of a million people have been killed in the war. Presidents Barack Obama and Vladimir Putin are expected to discuss the cease-fire by telephone and an official announcement should come soon after.