WASHINGTON (Reuters) -U.S. President Donald Trump and Prime Minister Mark Carney on Friday had a conversation that both men described as productive, although the Canadian leader said Ottawa would be imposing retaliatory tariffs next week as promised.

The phone call was the first contact since Carney won the leadership of Canada's ruling Liberals on March 9. Carney has said that Trump's threat of tariffs is a betrayal of a once close economic and security relationship.

"It was an extremely productive call, we agree on many things, and will be meeting immediately after Canada's upcoming Election to work on elements of Politics, Business, and all other factors," Trump wrote on his social media platform Truth Social.

That work "will end up being great for both the United States of America and Canada," he added. 

Carney on Thursday vowed to transform Canada's economy to be less dependent on the United States. Trump's tariff announcement is expected on April 2. Ottawa has made clear for months that it will impose countermeasures. 

"The Prime Minister informed the President that his government will implement retaliatory tariffs to protect Canadian workers and our economy, following the announcement of additional U.S. trade actions on April 2, 2025," Carney's office said in a statement.

The United States and its northern neighbor have long been close allies and trading partners. But relations deteriorated after Trump, a Republican who took office in January, upended the relationship with tariff threats and repeated comments about annexing the country.

Trump referred to Carney as the Canadian prime minister rather than as the governor of the 51st U.S. state, the term he often used to describe former Prime Minister Justin Trudeau.

Carney said the two leaders had agreed to begin comprehensive negotiations about a new economic and security relationship immediately after an election on April 28.