U.S. President Donald Trump on Thursday threatened to impose a 50-percent tariff on all aircraft sold into the United States from Canada unless Canada "immediately" certifies business jets made by U.S. plane manufacturer Gulfstream.

Trump accused Canada of wrongfully refusing to certify Gulfstream models, including the Gulfstream 500, 600, 700 and 800.

"We are hereby decertifying their Bombardier Global Expresses, and all Aircraft made in Canada, until such time as Gulfstream, a Great American Company, is fully certified," Trump said in a social media post on Thursday.