Canadian PM is set to retaliate against tariffs levied by Donald Trump and criticized US officials over insults

• US politics live – latest updates

Mark Carney has rebuked Donald Trump’s administration and urged officials in Washington to “start being serious” amid escalating trade tensions between the US and Canada.

Days before Canada is due to retaliate against Trump’s sweeping tariffs with its own duties on US goods, the Canadian prime minister criticized US officials for insulting his country. “It is beneath their office,” he said.

US trade representative Jamieson Greer has a level-headed reputation but commerce secretary Howard Lutnick and White House adviser Peter Navarro also have key roles

Having reportedly read Victor Hugo’s Les Misérables, in French, during a military tour of duty in Iraq, Jamieson Greer considered himself an unlikely target for accusations of francophobia.

But Donald Trump’s US trade representative, hitherto one of the president’s less high-profile cabinet members, found himself in that uncomfortable position amid the acrimonious collapse of bilateral trade talks with Canada that now threatens to degenerate into an all-out trade war between the two close trading partners whose economies are tightly intertwined.

Avoiding US goods and services – from tech to whisky to air travel – has forced many to find a new way of living

For William McDonald, 38, a diesel mechanic from Thunder Bay, Ontario, “Canadian is always the first choice,” even if it means his weekly bills are higher.

“As soon as Trump started putting those tariffs on in February [last year], I started boycotting US goods,” he said. “Avoiding American products has driven my costs up, and I’m still happy to do it.

With the federal deficit near 6% of GDP and the national debt over $40tn, America’s fiscal position looks increasingly precarious

• Bessent ‘will lose’ battle with bond markets, ex-mentor warns

Are we seeing the first signs of panic in Donald Trump’s Treasury? The US is by far the world’s biggest debtor, and the steady rise in global long-term interest rates – which I have long argued was inevitable – is starting to cause real pain.

Until now, the Treasury secretary, Scott Bessent, has dismissed concerns about US debt, which recently surpassed $40tn, as a big nothingburger. Growth, in his telling, will be so spectacular the US will easily be able to meet its interest obligations without any significant tax rises or spending cuts, while the rest of the world will happily keep feeding it money. But if Bessent really believes that, why is he trying to strong-arm the bond market by fiddling with the maturity structure of government debt?