US President Donald Trump has signed an executive order seeking to change the name of Lake Ontario to Lake America.
The move comes after trade talks between the US and Canada collapsed last week, and the US imposed new 50% tariffs on $20bn (C$28bn) worth of Canadian goods. Canada will implement “dollar for dollar” counter tariffs next month.
Trump said the move was “official, effective immediately” and that his administration has “filed all the necessary papers” to rename the lake, which straddles both countries.
In response, Canadian Prime Minister Mark Carney said “things must be called by their name, and this lake is called Lake Ontario – today and forever”.
Trump has repeatedly posted threats about renaming the lake on social media amid the trade dispute.
Text of the executive order says it gives the US Department of the Interior 30 days to update the name change with the Geographic Names Information Service – the official repository of domestic geographic names in the US.
Carney noted that the name Lake Ontario could be traced back more than 400 years, adding that it preceded the formation of the Canadian Confederation and the US Declaration of Independence.
He wrote on social media: “We know that the United States is changing. Their trade relations, their foreign policy, their national monuments, their hydronyms.
“Canadian women and men also know that things must be called by their name, and this lake is called Lake Ontario – today and forever.”
When Trump took the White House in 2025, he signed a similar order that changed the Gulf of Mexico to the Gulf of America. Mexico has rejected the name change, arguing a single country cannot rename a shared body of international water.
It also led to a legal dispute between Mexico and tech giant Google, which renamed the gulf in its maps application.
In that case, Google Maps users in the US see “Gulf of America”, while those in Mexico see the “Gulf of Mexico”. Those in other countries see the “Gulf of Mexico (Gulf of America)”.
