Plus: A Medevac jet crashed into a residential Philadelphia neighborhood Friday evening, with six people on board. The black box has been recovered.

The United States has postponed planned 25 percent tariffs on Canadian and Mexican imports by a month, following 11th-hour calls between President Donald Trump and leaders from Canada and Mexico on Monday.

WASHINGTON— President Donald Trump on Saturday signed an order to impose stiff tariffs on imports from Mexico, Canada and China, drawing swift retaliation and an undeniable sense of betrayal from the country's North American neighbors as a trade war erupted among the longtime allies.