By Patricia Zengerle WASHINGTON, June 16 (Reuters) - President Donald Trump said on Tuesday he was willing to send his interim deal to end the war with Iran for review by the U.S. Congress, as lawmakers, including many of his fellow Republicans, said they were largely in the dark about the pact. The U.S.-Iran agreement, announced on Sunday, has spurred optimism that a conflict that has killed thousands and disrupted the global economy will soon end.