WASHINGTON - Newly sworn-in U.S. President Donald Trump said on Monday that he would declare illegal immigration a national emergency, send troops to the U.S.-Mexico border, and reinstate his "remain in Mexico" policy as part of a sweeping immigration crackdown.

U.S. President Donald Trump on Monday signed executive orders declaring illegal immigration at the U.S.-Mexico border a national emergency, designating criminal cartels as terrorist organizations, and targeting automatic citizenship for U.