U.S. President Donald Trump will not let up pressure on tariffson Mexico, Canada and China related to their handling of fentanyl, Commerce Secretary Howard Lutnick said on Sunday, despite recent holds put on announced tariff measures.

Trump at first imposed 25% tariffs on Canadian and Mexican exports to the U.S., then exempted the duties on Mexican- and Canadian-made vehicles being transported into the U.S. and later by week’s end delayed the tariffs on almost all items for four weeks until April 2.

Trump during his address to Congress said that Canada and Mexico ‘have allowed fentanyl to come into our country at levels never seen before.’

Trump extended his blanket tariff on Chinese goods to 20 percent this week, citing Chinese exports of illicit fentanyl.

"American importers pay the tariffs and then do everything they can to pass that cost on to American consumers," John Bolton said.