FILE PHOTO: A cargo ship full of shipping containers departs the port of Oakland at the San Francisco Bay, California, U.S., August 4, 2025. REUTERS/Carlos Barria/File Photo

By Maggie Fick and Alistair Smout

LONDON, Dec 1 (Reuters) - Britain and the United States are poised to agree to zero tariffs on pharmaceutical products, with an announcement due at the White House on Monday, according to two sources familiar with the matter.

The sources said the deal is expected to include an increase in the percentage of the state-run National Health Service (NHS) budget that is spent on medicines.

It will also involve a major change in the value appraisal framework at NICE, a UK government body that determines whether new drugs are cost-effective for the NHS, the sources said.

NICE's "quality-adjusted life year" measures the cost of a treatment for each healthy year it enables for a patient, with the upper threshold being £30,000 per year. That threshold is set to be increased by 25%, the sources said, speaking on condition of anonymity to discuss confidential talks between the governments.

The White House and the British government did not immediately respond to requests for comment.

British Science Minister Patrick Vallance had earlier flagged that trade talks with the United States would likely lead to higher government spending on some medicines.

He told lawmakers in October that "some degree of price increase is inevitable" for new, innovative medicines under the talks, though existing drugs and generics may not see the same rises.

U.S. President Donald Trump has pressed Britain and the rest of Europe to pay more for American medicines, part of his push for U.S. medicine costs to be brought more in line with those paid in other wealthy nations.

Major pharmaceutical firms have meanwhile delayed investment in Britain, including AstraZeneca, the largest firm on the London Stock Exchange by market value, citing a tough operating environment.

The two countries agreed in May to seek "significantly preferential treatment outcomes on pharmaceuticals," with a commitment that Britain tries to improve the environment for pharma firms operating in the country.

(Reporting by Maggie Fick and Alistair SmoutEditing by Bernadette Baum and Frances Kerry)