US President Donald Trump on Monday announced a 50 percent tariff on most imports from Canada, accusing the neighbouring country of unfair trade practices involving automobiles, alcoholic beverages and dairy products.

The move is expected to heighten trade tensions between the two long-standing allies and could add pressure on prices while further straining bilateral economic relations.

A senior US administration official said Canada, along with China, was among the few countries to retaliate against previous US tariffs, prompting the latest action. The official spoke on condition of anonymity while briefing reporters ahead of the announcement.

According to the White House, Trump signed three proclamations under Section 338 of the US Trade Act of 1930, authorising the new tariffs.

The administration said the 50 percent duties will apply to most Canadian goods, including products that had previously enjoyed tariff-free access under the United States-Mexico-Canada Agreement (USMCA).

However, the tariffs will not apply to energy products, potash, fish and critical minerals.

The USMCA, which came into effect in 2020, was not renewed by the United States, leading to a fresh round of trade negotiations that could continue until 2036.

The White House said the new tariffs will take effect in 30 days, leaving room for possible negotiations before the measures are implemented.

Responding to the announcement, Canadian Prime Minister Mark Carney reaffirmed his country's commitment to free and fair trade and said Canada remains ready to negotiate with Washington.

In a statement, Carney noted that Canada had signed more than 20 new economic and security partnerships and expressed hope that outstanding trade issues with the United States could be resolved through dialogue.

He also warned that the trade dispute has increased costs for families, particularly in the United States, and said both countries would benefit from a negotiated solution.