U.S. President Donald Trump has issued a fresh warning to Canada after trade negotiations between the two countries broke down.

In an interview on Wednesday, Trump said it was “time to teach Canada you can’t do this anymore,” arguing that the United States could obtain goods from other countries if necessary.

The comments come after the United States imposed new 50% tariffs on about $20 billion worth of Canadian imports following the collapse of negotiations. Canada has announced retaliatory measures in response, with additional tariffs scheduled to take effect on September 8.

Trump has also threatened to increase tariffs on Canadian automobiles, trucks and auto parts to 50% starting January 1, 2027, adding further pressure to an already strained trading relationship.

Canadian Prime Minister Mark Carney has defended Canada’s position, saying Ottawa is prepared to protect Canadian businesses and workers while continuing to respond to the U.S. tariffs.

The latest developments have increased concerns that the dispute could become a prolonged trade conflict between the two closely connected economies. Reuters reports that there are currently no formal negotiations underway, although officials on both sides have left open the possibility of future talks.