Canadians have clapped back after US President Donald Trump threatened to change the name of Lake Ontario to “Lake America” amid an escalating trade war between the two countries.

“The United States is giving serious consideration to changing the name of Lake Ontario to Lake America in that we don’t expect to doing much business with Ontario any longer,” Trump declared on social media on Tuesday (local time).

The White House Instagram account also shared a photo of a map of the US that appeared to have been created using Lego bricks, with the words “Lake America” shown above the Great Lakes region and the Gulf of Mexico labelled “Gulf of America”.

Trump’s wild threat has been likened to his previous unilateral action in 2025 when he signed an executive order to rename the Gulf of Mexico the Gulf of America.

The President’s new post comes as the US and Canada are locked in a bitter trade dispute, with the Trump administration enacting 50 per cent tariffs on $US20 billion ($28 billion) of Canadian goods at the weekend after talks between the countries broke down.

Asked by reporters if there was anything Canada could do to stop Trump renaming Lake Ontario, Canadian Industry Minister Mélanie Joly replied:

“We’ll always call it Lake Ontario.”

Donald Trump posted this image on his Truth Social account.

After giving a bemused shrug as people at the press conference applauded, Joly added that Canada was proud of its Great Lakes.

“We’ve navigated the St Lawrence River, the Great Lakes, for thousands of years, and it was part of a foundation of our country. And we’ll just stand up for what we have.”

The Minister then made reference to the trade dispute: “Meanwhile, I think while all these shenanigans are happening, we’ll just be smart and we’ll be strategic and we’ll fight back.”

Ontario Premier Doug Ford told CNN that Trump’s threats were a “lot of rhetoric”.

“We’re strong believers in being a sovereign country, and when President Trump wants to attack our sovereignty and attack our businesses and people in Ontario, I can’t roll over,” he told the network’s Wolf Blitzer.

“My job is to protect Ontario and Canada, and ironically, protecting the American people.”

Canadian residents and social media users also bit back, with one quipping, “I’m thinking to rename USA as Old Mexico”, while another commented on the Lego map: “Sure as hell isn’t my America, DC ain’t even in the right place.”

 

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The official US-Canada border stretches across the water between Lake Ontario’s northern and southern shores.

The body of water forms much of New York State’s coastline and separates Buffalo from Toronto, the capital of the province of Ontario.

The lake’s name comes from the Huron Indigenous people’s word “oniatarí:io”, which means “lake of shining waters”, and it predates European settlement in the region. The province, founded in 1867, took its name from the lake.

Toronto mayoral candidate Brad Bradford joined those rebuffing the US President’s threat to rename Lake Ontario, joking on social media that if he was elected he would change New York’s name to “the Province of New York”, in line with its colonial roots.

“I’m even happy to send him a plaque,” Bradford said.

“When President Trump retires, and he can’t retire soon enough, he’ll be able to look out his window, way up in Trump Tower and see the great Province of New York.”

He wants to rename Lake Ontario.

So I’ve got a new name for his home state.

And yes, it’s historically accurate. pic.twitter.com/aLJMlz6Lja

— Brad Bradford (@BradMBradford) August 25, 2026

Although Trump has wide latitude over how the US government recognises geographic places and landmarks, he can’t actually force Canada to follow his preferred naming conventions.

However, his threat – made just hours before Canadian Prime Minister Mark Carney’s scheduled announcement of reciprocal tariffs on US imports into his country – shows how much the previously warm relationship between Washington and Ottawa has deteriorated.

Canada hit back on Wednesday with retaliatory tariffs on US annual imports and rolled out aid for businesses and workers, matching Washington’s latest duties dollar-for-dollar.

The counter-tariffs on US goods worth about $US20 billion ($A28 billion) take effect on September 8 and impose duties of 15 per cent, 25 per cent and 50 per cent across around 700 products imported from south of the border, a government statement said.

“Our dollar-for-dollar, rate for rate counter-tariffs, ⁠as well as a multi-billion dollar support package, will protect workers, farmers, families, and businesses,” Canada’s Finance Minister François-Philippe Champagne said.

Canada levied the 50 per cent tariffs on steel, aluminium, furniture and clothing, set the 25 per cent tariffs on cheese, appliances and some seafood, and placed the 15 per cent tariffs on electronics and tools, a Canadian government official said.

–with AP / Reuters