FILE PHOTO: U.S. President Donald Trump speaks during a briefing on "drug trafficking on the southern border" in the Roosevelt Room at the White House in Washington, U.S. March 13, 2019. REUTERS/Jonathan Ernst

WASHINGTON (Reuters) - U.S. President Donald Trump said on Thursday he would reject legislation that would end his national emergency declaration at the U.S. border, if the bill passes the U.S. Senate.

“I am prepared to veto, if necessary,” Trump said in an early morning tweet sent as the Senate prepared to take up the measure later on Thursday.