Trump threatens Lake Ontario name change amid trade war

President Donald Trump is considering changing the name of Lake Ontario to "Lake America" as the trade war between the United States and Canada intensifies.

Such a change would be reminiscent of the Republican president's unilateral action in 2025 by executive order to rename the Gulf of Mexico to the Gulf of America.

The United States and Canada are locked in a trade dispute, with Canada expected Tuesday to announce retaliatory measures after the Trump administration enacted 50 per cent tariffs on $US20 billion ($A28 billion) of Canadian goods at the weekend after talks between the countries broke down.

"The United States is giving serious consideration to changing the name of Lake Ontario to Lake America in that we don't expect to (be) doing much business with Ontario any longer," Trump said on social media on Tuesday.

Ontario is Canada's most populous province and is home to the country's auto industry.