Jami` at-Tirmidhi 1122

Muhammad bin Ka'b narrated that:Ibn Abbas said: "Mut'ah was only during the beginning of Islam. A man would arrive in a land that he was not familiar with so he would marry a woman for the extent of time that he thought he would remain there. So his Mut'ah was upheld and his case was fine until the (following) Ayah was revealed: Except their wives or what their right hands possess. Then every private part other than those became unlawful