Canadian prime minister Mark Carney has urged citizens to back domestic businesses and workers under a new “Buy Canadian” policy, hours after US President Donald Trump threatened to impose 100 per cent tariffs on Canadian goods if Ottawa proceeded with trade deals with China.In a video posted on his X account, Carney framed the policy as a response to growing economic pressure from abroad.“With our economy under threat from abroad, Canadians have made a choice: to focus on what we can control. You’re choosing to put your hard earned dollars behind Canadian businesses, and Canadian workers,” he said. “Canada’s new government is doing the same with our new Buy Canadian Policy.” Carney said the government would prioritise domestic sourcing for major national projects, including housing, infrastructure and defence.“We’re aiming to build big, from millions of homes that will improve affordability to major projects that will transform our economy, to new military hardware that will protect Canadians and our sovereignty,” he said.He went on to add, “To build big from Canadian material, Canadian steel, aluminium, lumber, with Canadian technology and Canadian workers… Buy Canadian, build Canadian and together we will build Canada strong.” The statement came shortly after Trump issued a warning to Ottawa over closer economic engagement with Beijing. Writing on Truth Social, Trump referred to Carney as “governor” and said the US would retaliate if Canada entered into trade arrangements with China.“If Governor Carney thinks he is going to make Canada a ‘Drop Off Port’ for China to send goods and products into the United States, he is sorely mistaken,” Trump said. “If Canada makes a deal with China, it will immediately be hit with a 100% Tariff against all Canadian goods and products coming into the USA.”Trump also claimed China would “eat Canada alive” and accused Ottawa of undermining US interests. Earlier, he criticised Canada for opposing his proposed “Golden Dome” missile defence system over Greenland while pursuing deeper economic ties with Beijing.The sharp exchange followed Carney’s recent visit to China – the first by a Canadian leader in nearly a decade – where he sought to revive economic engagement with Canada’s second-largest trading partner after the US. The visit resulted in agreements to reduce tariffs on select Canadian agricultural exports and introduce quotas on Chinese electric vehicle imports, with the possibility of increased Chinese investment.Chinese President Xi Jinping welcomed the visit as a “turnaround” in bilateral relations. Speaking earlier about the agreement, Carney pointed to ongoing US tariff tensions, describing Canada’s talks with Beijing as more “predictable” and characterising the discussions as “realistic and respectful.”Trump’s comments have further heightened trade tensions between Washington and Ottawa, even as Carney’s government signals a sharper focus on domestic manufacturing and supply chains amid an increasingly uncertain global trade environment.