OTTAWA — U.S. President Donald Trump signed an executive order Thursday renaming Lake Ontario “Lake America” for official U.S. federal use, following through on a threat made as his trade war with Canada escalates.The order updates the name used by the U.S. geographic naming system and federal agencies. It has no authority over Canadian usage, meaning the shared Great Lake will remain Lake Ontario in Canada.“So this is Lake Ontario in Canada and in the United States, but we’re going to make a little change,” Trump said while marking up a map in the Oval Office.“We’re going to call it something different than Lake Ontario. We’re going to call it Lake America.”Trump crossed out Lake Ontario on the map and wrote the new name in its place.“So Lake Ontario, that’s gone,” he said. “Lake America. So now we have a lake and now we have a Gulf, because we have the Gulf of America and now we have Lake America.”.Trump first threatened the change Tuesday, saying the United States was giving it “serious consideration” because it did not expect to conduct much business with Ontario in the future.He reiterated the possibility Wednesday during an interview with conservative radio host Glenn Beck.“People thought I was kidding,” Trump said. “Maybe I wasn’t, because the last one you saw was the Gulf of Mexico. It’s now the Gulf of America.”Lake Ontario straddles the Canada-U.S. border, with Ontario to the north and New York state to the south. Trump cannot require Canada, international organizations, private mapmakers or individual Americans to adopt the name.The order mirrors Trump’s 2025 decision directing the U.S. government to refer to the Gulf of Mexico as the “Gulf of America.”Thursday’s action is the latest escalation in the deteriorating relationship between Canada and the United States.Prime Minister Mark Carney suspended trade negotiations with Washington last week, saying last-minute U.S. demands were “unfair, uneconomic” and called the reliability of any agreement into question.The United States subsequently imposed 50% tariffs on roughly $28 billion in Canadian goods, with Canada announcing matching countermeasures.Trump has also threatened to raise tariffs on Canadian cars, trucks, automotive parts and steel to 50% on January 1, 2027.The president linked his original Lake Ontario threat directly to the dispute with Ontario after Premier Doug Ford told Trump to “kiss my ass” and threatened higher prices on oil and critical minerals exported to the United States.