WASHINGTON (AP) — President Barack Obama welcomed an agreement Saturday to secure and destroy Syria’s chemical weapons stockpile as an “important, concrete step” toward the ultimate goal of eliminating them but warned that the U.S. remains prepared to act if the attempt at a diplomatic solution fails.

Obama said the deal between the U.S. and Russia offers the chance to destroy weapons the U.S. and more than 30 governments maintain were used by President Bashar Assad to kill more than 1,400 Syrians during an attack last month in the suburbs of the capital of Damascus.