US President Donald Trump has accused Canadian Prime Minister Justin Trudeau of leveraging the Canada-US trade war to maintain his grip on power.

The claim came after the two leaders had a “somewhat friendly” phone call on Wednesday.

In a social media post, Trump stated that Trudeau “was unable to tell me when the Canadian election is taking place, which made me curious, like, what’s going on here? I then realized he is trying to use this issue to stay in power.”

Despite Trudeau’s announcement in January that he would resign, he remains in office until a Liberal Party leadership contest this weekend determines his successor.

The new Liberal leader will also become prime minister and gain the authority to call the next federal election, which must occur by October but could be held earlier.

Trudeau and Trump have had a fractious relationship since Trump returned to the White House in January, frequently clashing over trade and fentanyl trafficking.

The tension escalated further on Tuesday when Trump imposed 25% tariffs on Canadian imports to the United States. In response, Trudeau remarked that while he considers Trump a “smart guy,” the tariffs are a “very dumb thing to do.”

Trudeau also accused Trump of attempting to weaken the Canadian economy to make annexation easier, a reference to Trump’s past remarks about making Canada the 51st American state.

Adding to the tension, Trump has repeatedly referred to Trudeau as “Governor Trudeau”, signaling a dismissive stance towards the Canadian leader.