President Donald Trump has signed an executive order to rename Lake Ontario “Lake America,” escalating a growing dispute with Canada.
Trump signed the order and said the new name would take effect immediately, although the formal process requires the US Department of the Interior and the Board on Geographic Names to update federal records within 30 days.
The move applies to US government usage and cannot compel Canada to adopt the new name for the binational lake.
Lake Ontario is one of North America’s five Great Lakes and is shared by the US state of New York and the Canadian province of Ontario.
The lake covers about 7,340 square miles and forms an important link in the Great Lakes–St. Lawrence waterway, supporting shipping, recreation, fisheries and other economic activities on both sides of the border.
Under the executive order, Interior Secretary Doug Burgum is directed to work with the Board on Geographic Names to update the US Geographic Names Information System and remove references to “Lake Ontario” from federal government maps, documents, contracts and other official communications.
Trump justified the decision by highlighting what his administration describes as the United States’ contribution to protecting and maintaining the Great Lakes.
The order says the US Coast Guard provides nine of the 11 icebreaking vessels operating on the Great Lakes and cites nearly $4 billion in US investment in protecting the lakes’ freshwater ecosystem over the past decade.
The announcement comes at a particularly tense moment in US-Canada relations. Trade negotiations between Washington and Ottawa have broken down, with the Trump administration imposing 50 per cent tariffs on about $20 billion worth of Canadian imports.
Canada has announced retaliatory measures covering more than 700 US products, with the measures scheduled to take effect on September 8.
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Trump has repeatedly criticized Canada over trade and, while announcing the renaming, said Canadian officials had treated the United States “very badly.”
He has also previously suggested that the name change was something he had been considering for some time, rather than solely a response to the latest trade dispute.
Canadian officials, however, have rejected the proposed name. Prime Minister Mark Carney said the body of water would remain Lake Ontario, pointing to the name’s Indigenous origins and long history.
The name is derived from an Indigenous term associated with the lake and predates the creation of the modern province of Ontario and the establishment of the United States.
The renaming follows a broader effort by Trump to change the names of prominent geographical features. In January 2025, shortly after returning to office, he ordered the federal government to refer to the Gulf of Mexico as the “Gulf of America” and restored the name Mount McKinley for Alaska’s highest peak, reversing the federal use of the name Denali.
The Gulf of Mexico decision similarly highlighted the limits of US naming authority beyond American government usage.
While US federal agencies adopted “Gulf of America,” Mexico and other international users have continued to use “Gulf of Mexico.”
The same distinction is expected to apply to Lake Ontario, with Canada under no obligation to recognize the US designation.
Trump also used the announcement to float the possibility of renaming other major bodies of water. Referring to the Atlantic and Pacific oceans, he joked that after changing the name of a gulf and a lake, “all we need is an ocean,” suggesting that both could potentially be given new names.
The latest move is therefore largely symbolic, but it adds another point of friction to an already strained US-Canada relationship.
For the United States, federal maps and official documents are expected to begin using “Lake America,” while in Canada, the historic name “Lake Ontario” is expected to remain in use.
Al Jazeera
