U.S. President Donald Trump talks to reporters as he departs for travel to New Jersey from the South Lawn of the White House in Washington, U.S., July 5, 2019. REUTERS/Carlos Barria

WASHINGTON (Reuters) - President Donald Trump said on Friday that he is considering an executive order to add a contentious question about citizenship to the 2020 U.S. Census, after a U.S. Supreme Court blocked his initial effort to include it.