President Donald Trump signed an executive order on Saturday that orders an investigation into U.S. imports of wood products, an industry that the president sees as “essential to the national security,

In his third new tariff probe in a week, Trump signed a memo ordering Commerce Secretary Howard Lutnick to initiate a national security investigation into U.S. lumber imports under Section 232 of the Trade Expansion Act of 1962.

A senior White House official, who spoke to The Associated Press on condition of anonymity, said that Canada, Brazil and others are engaged in subsidies regarding lumber that put the United States at a disadvantage.