We've been poised to bring you lines from Canadian Prime Minister Justin Trudeau, who is due to deliver a news conference to discuss Canada's response to Trump's tariffs shortly.

After some delays, we're currently expecting him to appear at 21:00 local time (02:00 GMT).

You can watch the event at the top of this page by clicking the Watch Live button.

Asia business reporter

Businesses in South East Asia are watching the news of tariffs closely. Their supply chains reach as far as Mexico and Canada, because of the proximity to the final destination for some of their exports - the US.

But the region relies on China’s might and it’s still the number one place to source materials, equipment and components from. Malaysia, Singapore and Thailand are key players in the region’s electronics supply chain. The Philippines and Vietnam play important roles in assembly too.

It would be costly and difficult to completely remove China from a production process. But with Trump forging ahead with 10% tariffs on Beijing, and retaliatory tariffs on American products expected, supply chains could be upended, leading to shortages.

We’ve been here before - Trump imposed punitive duties on Chinese goods in 2018 and 2019, and that lead to some production moving out of China to South East Asia. With fresh tariffs on China, Mexico and Canada, there could be further restructuring of manufacturing ecosystems.

Mexico's President Claudia Sheinbaum says retaliatory measures including tariffs will be introduced on the US following President Donald Trump's announcement imposing 25% tariffs on all Mexican imports.

"I instruct the Secretary of Economy to implement Plan B that we have been working on, which includes tariff and non-tariff measures in defence of Mexico's interests," she writes on X, providing no further details of what these will be.

She also calls out the categorisation of her government as having alliances with criminal organisations as "slander".

BBC business reporter

The US Retail Industry Leaders Association, which includes big names such as Home Depot, Target and Walgreens among its more than 200 members, has expressed hope it is still not too late for tariffs to be averted.

It says: “We understand the president is working toward an agreement. The leaders of all four nations should come together and work to reach a deal before Feb. 4 because enacting broad-based tariffs will be disruptive to the U.S. economy.“

It warns that if US tariffs on China, Mexico and Canada do go ahead it risks pushing up prices for US consumers in the shops.

That’s something we've heard from many leading economists and major Wall Street banks.

US inflation rose to 2.9% in December. The US central bank, the Federal Reserve, has been struggling to get it back down to its 2% target.

BBC News, Toronto

British Columbia Premier David Eby has called the US levies on Canadian goods a "complete betrayal of the historic bond" between the two nations.

In a televised statement on Saturday night, he says it is a "declaration of economic war against a trusted ally and friend".

All provincial liquor stores will stop buying American liquor from US "red states" in response to the tariffs and will be removing those brands from shelves, he says. It would be a first step in their response, he adds.

The province of Ontario is also considering pulling US booze from shelves.

Eby says he is sympathetic to President Donald Trump's concerns about fentanyl. British Columbia is one of the Canadian provinces hardest hit by the opioid crisis.

"We all need to work together on this global problem, this isn't the way to do it," he says.

His province is one of the least exposed to trade with the US but he says the tariffs will nonetheless be "profoundly damaging".

About 54% of British Columbia's exports go to the US.

Canadian Prime Minister Justin Trudeau says Canada "did not want this" but is "prepared" to respond to Trump's tariff announcement.

"The United States has confirmed that it intends to impose 25% tariffs on most Canadian goods, with 10% tariffs on energy, starting February 4," he writes on X.

"I’ve met with the Premiers and our Cabinet today, and I’ll be speaking with President Sheinbaum of Mexico shortly.

"We did not want this, but Canada is prepared. I’ll be addressing Canadians later this evening."

We're currently expecting Trudeau to deliver a press conference at 20:30 eastern time (01:30 GMT).

Ahead of that, press conferences are being held by Canadian province leaders. We'll bring you more on that next, but in the meantime you can tune into them by pressing the Watch Live button at the top of this webpage.

Reporting from Mexico City

In essence, the imposition of 25% tariffs on Mexican goods has been expected by the Mexican government from the moment Donald Trump won the presidency. In recent days, President Claudia Sheinbaum has called for “cool heads” in dealing with the trade dispute – and with Washington more generally – under President Trump.

On Friday, her Finance Minister, Marcelo Ebrard, a former foreign minister with first-hand experience of the first Trump administration, suggested tariffs would be more harmful to the US given it imports everything from avocados to car parts from Mexico. The Mexican government considers a trade war as unwelcome, unwise and avoidable, especially between supposedly friendly neighbours and close allies.

Yet despite the apparent calm in Mexico City, there will no doubt be some dismay at the aggressive tone of the statement from the White House. It accuses the Sheinbaum government of having “an intolerable alliance” with Mexican drug trafficking organisations and of providing “safe havens for the cartels to engage in the manufacturing and transportation of dangerous narcotics”.

Few Mexicans are under any illusions of the extent of the complicity between corrupt local and state forces and politicians and the country’s cartels.

But Sheinbaum has only been in office since October and has chosen as her Public Security Minister, Omar Garcia Harfuch, a former police officer with strong credentials for the role.

The Mexican government might have hoped for a different start to the dialogue with the US on the toughest issues of their shared border – namely undocumented immigration and fentanyl trafficking. But the Trump administration, and Trump himself, believes tariffs are an effective way to bring Mexico to the negotiating table – with Washington in the dominant position.