President Donald Trump threatened to decertify Canadian-made aircraft and impose a 50% tariff unless Canada approves Gulfstream jets, accusing Ottawa of illegally blocking certification while allowing its own planes access to the American market. The dispute centers on aircraft certification, a regulatory process that determines whether planes can be sold and operated in a country. Trump has accused Canadian authorities of using that process to restrict U.S.-made Gulfstream jets. "Further, Canada is effectively prohibiting the sale of Gulfstream products in Canada through this very same certification process." Data provider Cirium said 150 Global Express aircraft are registered in the United States and operated by 115 different operators.