US President Donald Trump has signed an executive order renaming Lake Ontario as “Lake America” for official US federal use, in the latest escalation of his dispute with Canada.
Trump signed the order on Thursday at the White House, saying the change was effective immediately. The order directs the US Department of the Interior to update federal geographic records and naming systems.
Trump justified the move by accusing Canada of treating the United States unfairly in trade and defence. He said Canada had been “ripping us off” in trade and criticised Ottawa over its relationship with Washington. 
However, the order does not require Canada or international organisations to adopt the new name. Lake Ontario is shared by the US state of New York and Canada’s province of Ontario, with more than half of its surface area lying in Canadian territory.
Ontario Premier Doug Ford dismissed the move, saying the lake would continue to be known as Lake Ontario by Canadians and much of the rest of the world.
The renaming comes amid a rapidly worsening US-Canada trade dispute. Washington recently imposed 50 per cent tariffs on about $20 billion worth of Canadian goods, while Canada responded with retaliatory tariffs of its own on hundreds of US products.
The latest move echoes Trump’s decision in January 2025 to rename the Gulf of Mexico as the “Gulf of America” for US federal purposes.
Trump also suggested that further geographic name changes could be considered, joking that after a gulf and a lake, the United States might eventually rename the Atlantic or Pacific Ocean.
Canadian Prime Minister Mark Carney’s government had not immediately issued a formal response to the latest order.
The controversy has added another symbolic dimension to already strained relations between the two neighbouring countries, as both sides continue to impose tariffs and seek to protect their economies.
