Trump made his threat in social media posts, announcing huge import tariffs against neighbours Canada and Mexico, and also rival China if they don’t stop illegal immigration and drug smuggling into the US.

China responded that “no one will win a trade war,” while Mexican President Claudia Sheinbaum warned that “for every tariff, there will be a response in kind.”

A Canadian government source said Prime Minister Justin Trudeau called Trump and had a “productive” discussion, without giving further detail.

Such tariffs threaten to disrupt the global economy, deepen already fierce tensions with China, and upend relations with the US’s two largest neighbours.

Nervous stock markets saw “volatile trading conditions” as they digested the news, said an analyst at City Index, Fawad Razaqzada.

On his Truth Social platform, Trump said late Monday that he would enact the tariffs when he takes office on January 20, 2025, if his — vaguely worded — demands were not met.

The posts signal Trump’s intention to return to the governing style of his first presidency when he regularly shocked Washington and US partners with abrupt, major policy shifts which he announced on social media.

They also confirmed that Trump is serious about his major campaign promise to use the US economic muscle as leverage on issues having little to do with trade — namely his claim that the US is under siege by foreign crime and dangerous migrants.

On Tuesday, Trump named two important figures to his economic team: Jamieson Greer as his trade representative and Kevin Hassett as his top economic advisor, heading the White House National Economic Council.

Both had roles in his first administration, with Greer serving as the Chief of Staff to former US Trade Representative Robert Lighthizer.

“I will sign all necessary documents to charge Mexico and Canada a 25 per cent tariff on all products coming into the United States,” Trump earlier posted.

“This tariff will remain in effect until such time as drugs, in particular Fentanyl and all illegal aliens stop this invasion of our country!” he said.

In another post, Trump said he would be slapping China with a 10 per cent tariff, “above any additional tariffs,” because the world’s second-biggest economy was failing to execute fentanyl smugglers.

The spokesman for China’s embassy in the US, Liu Pengyu, told AFP, “China believes that China-US economic and trade cooperation is mutually beneficial in nature.”

Mexico’s Sheinbaum fired back at Trump, saying his tariffs diplomacy was “not acceptable” and based on erroneous claims.

“It is not with threats or tariffs that the migration phenomenon will be stopped, nor the consumption of drugs in the United States,” she said.

Sheinbaum pointed out that the Mexican narcotics industry largely exists to serve demand in the US.

“Seventy per cent of the illegal weapons seized from criminals in Mexico come from your country.

“Tragically, it is in our country that lives are lost to the violence resulting from meeting the drug demand in yours,” she said.

– Bluster or serious? –

A senior adviser at the Centre for Strategic and International Studies, William Reinsch, said Trump’s online threats may be bluster — a strategy of “threaten and then negotiate.”

However, Trump’s first White House term was marked by an aggressive and protectionist trade agenda that also targeted China, Mexico and Canada, alongside Europe.

While in office, Trump launched an all-out trade war with China, imposing significant tariffs on hundreds of billions of dollars of Chinese goods.

China responded with retaliatory tariffs on American products, particularly affecting US farmers.

Economists say tariffs can hurt US growth and fuel inflation since they are paid by importers who often pass those costs on to consumers.

Trump has said he would put his Commerce Secretary-designate Howard Lutnick, a China hawk, in charge of trade policy.

AFP