Ottawa, Canada - Canadian Prime Minister Mark Carney responded to President Donald Trump's bizarre decision to rename Lake Ontario by lecturing him on North American history.

"The name Lake Ontario comes from the Wendat word Ontari’io, which, appropriately, means 'the lake is beautiful, the lake is big,'" Carney wrote in a post to X on Thursday.

"The name is more than 400 years old, predating both the Confederation of Canada and the Declaration of Independence of the United States of America," he explained.

"We know that America is changing. Their trading relationships, their foreign policies, their national monuments, their hydronyms. Canadians also know that naming reality means calling it Lake Ontario – then, now and always."

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Carney's comments came hours after Trump used a press conference in the Oval Office to announce he's officially changing Lake Ontario's name to "Lake America."

The move came amid an escalating trade war with Ottawa, which has seen both nations implement tit-for-tat sanctions after Carney's government last week walked away from an "unfair" trade deal.

"The Canadian officials have treated us very badly. They're nasty people," Trump said Thursday. "The lake change, Lake of America, was something I've been thinking about for a long time."

Carney is not the only Canadian leader to have slapped back.

Ontario Premier Doug Ford, a vocal Trump critic, declared on X: "It's Lake Ontario to Canadians and the rest of the world. Now and forever."

Grand Chief Pierre Picard, a spokesperson for the Wendat Nation, said on Thursday he is "outraged, appalled, shocked" at Trump's decision.

"For our Nation, the name Ontario embodies history, culture, and identity. To call this name into question is an abhorrent and unspeakable act," he said.

"Just like his presidency, this name change once again sows confusion and strikes a direct blow to the very heart of our Wendat identity."