"Beginning today the United States of America gets back control of its borders," Trump declared during a visit to the Department of Homeland Security. "We are going to save lives on both sides of the border.
The actions, less than a week into Trump's presidency, fulfilled pledges that animated his candidacy and represented a dramatic redirection of U.S. immigration policy. They were cheered by Republicans allies in Congress, condemned by immigration advocates and triggered immediate new tension with the Mexican government.
"I regret and reject the decision of the U.S. to build the wall," Mexican President Enrique Pena Nieto said Wednesday in a nationally televised address.
Trump is expected to wield his executive power again later this week with the directive to dam the refugee flow into the U.S. for at least four months, in addition to the open-ended pause on Syrian arrivals.