WASHINGTON (TNND) — President Donald Trump signed an executive order directing the U.S. government to use the name “Lake America” for Lake Ontario, stating the change would be immediate during his Thursday announcement.

Trump had floated the name change in a Truth Social post Tuesday, writing that the United States was giving “serious consideration” to renaming Lake Ontario because it did not expect to do much business with Ontario any longer.

The executive order makes the change official for U.S. federal use, following Trump’s previous move to rename the Gulf of Mexico as the Gulf of America in U.S. government materials.

The action comes as the Trump administration’s trade dispute with Canada intensifies. The U.S. recently imposed 50% tariffs on $20 billion in Canadian goods after talks between the two countries broke down, and Canada has announced retaliatory measures.

Lake Ontario sits along the U.S.-Canada border, with New York on its southern shore and the Canadian province of Ontario to the north. While the president can direct how U.S. agencies refer to geographic features in federal documents and maps, the order does not require Canada, international organizations or the public to use the new name.

Canadian officials and residents had already dismissed Trump’s proposal before the order was signed.

Ontario Premier Doug Ford called the earlier idea “a lot of rhetoric” and urged both countries to return to trade negotiations. Others pointed to the lake’s deep historical ties to the region: Its name comes from the Huron Indigenous word oniatarí:io, commonly translated as “lake of shining waters,” and predates both the United States and Canada.

The name change adds another symbolic flashpoint to a trade conflict that has taken on an increasingly personal tone between Trump and Canadian leaders.