Donald Trump has vowed to impose import taxes of 100 per cent on pharmaceutical drugs in his latest round of tariff plans.

The US president said on Truth Social that the new levies would hit all imported drugs from Oct 1 – but he said the taxes could be avoided by companies if they built manufacturing plants in America.

The move could particularly impact British companies, who export more than £5 billion in pharmaceutical products across the Atlantic every year.

Mr Trump also announced tariffs of 50 per cent on kitchen cabinets and bathroom vanities, 30 per cent on upholstered furniture and 25 per cent on heavy trucks.

It comes despite controversy over the legality of his tariffs, which have been a cornerstone of Mr Trump’s economic policy since he returned to the White House.

Last month a US court ruled that some of his taxes were illegal, potentially opening the way for the US Treasury to have to repay billions of dollars in levies.

Thursday’s announcement about pharmaceuticals has shocked the industry.

Mr Trump has previously suggested that tariffs would be phased in over time so that companies had time to build factories and relocate production. In August, the president said he would start by charging a “small tariff” on pharmaceuticals and raise the rate over a year or more to 150 per cent and even 250 per cent.

He said on Truth Social that the pharmaceutical tariffs would not apply to companies that are building factories in the US, which he defined as either “breaking ground” or being “under construction.” It was unclear how the tariffs would apply to companies that already have factories in the US.

In 2024, America imported nearly $233 billion (£175 billion) in pharmaceutical and medicinal products, according to the Census Bureau. The prospect of prices doubling for some medicines could be alarming to voters as healthcare expenses, as well as the costs of Medicare and Medicaid, potentially increase.

According to the White House, the threat of tariffs earlier this year contributed to many major pharmaceutical companies, including Johnson & Johnson, AstraZeneca, Roche, Bristol Myers Squibb and Eli Lilly, among others, to announce investments in US production.

Despite criticism from economists and world leaders, Mr Trump remains committed to tariffs which he claims will help to reduce the government’s budget deficit while increasing domestic manufacturing.

On Thursday he claimed that the taxes on imported kitchen cabinets and sofas were needed “for National Security and other reasons.”

The new tariffs on cabinetry could further increase the costs for homebuilders at a time when many people seeking to buy a house feel priced out by the mix of housing shortages and high mortgage rates.

In addition, Mr Trump said that foreign-made heavy trucks and parts are hurting domestic producers that need to be defended.

“Large Truck Company Manufacturers, such as Peterbilt, Kenworth, Freightliner, Mack Trucks, and others, will be protected from the onslaught of outside interruptions,” Mr Trump posted.

The tariffs are another dose of uncertainty for the US economy amid a weakening outlook for jobs and elevated inflation.

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These new taxes on imports could pass through to consumers in the form of higher prices and dampen hiring, a process that economic data suggests is already underway.

Jerome Powell, the chair of the Federal Reserve, has warned that higher costs for goods account for “most” or potentially “all” of the increase in inflation levels this year.

The US president has pressured Mr Powell to resign, arguing that the Fed should cut its benchmark interest rates more aggressively because inflation is no longer a concern. Fed officials have stayed cautious on rate cuts because of the uncertainty created by tariffs.

Mr Trump continues to claim that inflation is no longer a challenge for the US economy, despite evidence to the contrary. The consumer price index has increased 2.9 per cent over the past 12 months, up from an annual pace of 2.3 per cent in April, when the White House first launched a sweeping set of import taxes.

His broader country-by-country tariffs relied on declaring an economic emergency based on a 1977 law, a drastic tax hike that two federal courts said exceeded Mr Trump’s authority as president. The Supreme Court is set to hear the case in November.

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