Canada will implement dollar-for-dollar retaliatory tariffs on United States goods from 8 September, Prime Minister Mark Carney has announced, following the collapse of bilateral trade negotiations and the imposition of fresh 50% US duties on Canadian products.

Speaking on Saturday, Mr Carney described the latest US measures as a "miscalculation" and warned that Canada was now in a trade "war". He said his government was retaliating "reluctantly" after US negotiators presented unacceptable demands, telling Canadians that Washington "asked too much and they offered too little".

We previously reported that the timeline and specific sectors targeted by Canada were unknown. It is now confirmed that the retaliatory measures taking effect on 8 September will target US steel, dairy, appliances, and electronics, with full details of the counter-measures expected in the coming days. The new 50% US duties add to existing American tariffs on Canadian steel, aluminium, motor vehicles, and lumber.

The circumstances surrounding the breakdown in negotiations have also become clearer, with both sides trading accusations over last-minute changes. Mr Carney rejected claims that Canada had shifted its position, stating that the US had demanded restrictive terms that would limit Canada's ability to negotiate trade deals with other countries. Conversely, US Trade Representative Jamieson Greer told Fox News that Canada made "new demands and walk backs" on previously agreed terms, adding that there are currently no plans to restart talks. President Donald Trump has yet to comment publicly on the matter.

Domestically, Canadian political leaders have rallied behind the prime minister's response. Conservative opposition leader Pierre Poilievre called the latest US levies "unjustified", while British Columbia Premier David Eby warned that the proposed US trade restrictions would have reduced Canada to "the economic equivalent of the 51st state". Quebec Premier Christine Fréchette pledged provincial support for affected industries, warning that jobs would probably be lost.

The deterioration in US-Canada relations contrasts with diplomatic efforts elsewhere. While Canada prepares its reciprocal tariffs, Brazilian President Luiz Inácio Lula da Silva held a telephone discussion with President Trump on Friday seeking to reopen bilateral trade negotiations between Brazil and the US.

With Washington indicating no immediate plans to return to the negotiating table, the path towards resolving the dispute remains blocked. I will be following the rollout of Canada's full tariff schedule closely as the 8 September deadline approaches.