Asserting the U.S. Senate's constitutional role on treaties, Tennessee U.S. Senator Bob Corker sent the president a letter of warning. Tennessee's junior senator warns the Obama administration not to take any actions to implement the United Nations Arms Trade Treaty without senate advice and consent. Corker added the Arms Trade Treaty raises significant legislative and constitutional questions. News 2 spoke with the senator's Washington office and asked if there had been any response from the White House on the letter. So far there is no response.