AstraZeneca has unveiled plans to invest $50bn (£37bn) in the US by the end of the decade amid fears it could ditch the London stock market.

The British drugmaker said the huge investment in both medicines manufacturing and research and development will help fuel its aim of reaching $80bn in revenues by 2030, half of which will be generated in the US.

The announcement, which comes on top of a $3.5bn spending push announced late last year, will fuel speculation that the pharmaceutical giant is weighing up a move to the US.

Reports this month said Sir Pascal Soriot, AstraZeneca’s chief executive, had discussed moving the company’s listing to the US and shifting its domicile away from the UK. AstraZeneca has declined to comment on the reports.

The spending spree also comes in the wake of Donald Trump’s threats to impose tariffs of as much as 200pc on medicines imported to the US.

The US president has encouraged pharmaceutical companies to move their factories to America. Earlier this month he said he would give businesses “a year or so to build” before ramping up levies.

AstraZeneca said the cornerstone of its US investment plan would be a new drug manufacturing facility focused on chronic diseases.

The factory, to be built in Virginia, will mark the company’s largest single manufacturing investment to date.

The investment plan also includes the construction or expansion of manufacturing and research facilities in Maryland, Massachusetts, California, Indiana and Texas.

Howard Lutnick, the US secretary of commerce, said: “For decades, Americans have been reliant on foreign supply of key pharmaceutical products. President Trump and our nation’s new tariff policies are focused on ending this structural weakness.

“We are proud that AstraZeneca has made the decision to bring substantial pharmaceutical production to our shores. This historic investment is bringing tens of thousands of jobs to the US and will ensure medicine sold in our country is produced right here.”

While AstraZeneca is listed in London and headquartered in Cambridge, the US is its largest market, accounting for 42pc of revenues. The company already operates 19 sites and employs more than 18,000 people in the US.

Sir Pascal has grown increasingly frustrated with the UK in recent years, criticising its tax rates, high NHS rebates and refusal to buy new medicines.

In 2023, AstraZeneca said it had decided not to build a new $400m drug factory in Britain because of its “discouraging” tax regime, while last year it scrapped plans for a separate £450m vaccine facility in Liverpool after the Government cut the financial support available.

AstraZeneca is the largest listed business in the UK and any decision to move the company would come as an enormous blow to the London Stock Exchange, which is already reeling from a wave of departures and dearth of new listings.

It would also be an embarrassing setback for the Government, which last week published its long-awaited life sciences sector plan.

Sir Pascal said: “Today’s announcement underpins our belief in America’s innovation in biopharmaceuticals and our commitment to the millions of patients who need our medicines in America and globally. It will also support our ambition to reach $80bn in revenue by 2030.”

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