Donald Trump has aggressively pursued investment into hi-tech industries in recent months, but the US administration has now set its sights on a more traditional sector: tin mining in Cornwall.

The South Crofty mine, near the village of Pool, could start up again after nearly three decades aided by a potential $225m (£166m) investment from across the Atlantic, creating 300 jobs.

The site dates back to the 1600s but closed in 1998; there have since been repeated attempts to reopen it.

Cornish Metals, its owner, said on Thursday it had received a letter of funding interest from the official export credit agency of the US to develop the site. Any investment would depend on the mine supplying tin to the US, which considers the metal to be a critical mineral.

Tin is used for soldering and is found in most electronic devices, as well as electric cars and solar panels. The metal is important for connecting semiconductor chips to circuit boards and its value has surged amid the boom in investment in datacentres that will power the AI industry.

The metal’s price has risen sharply over the last decade, from $16,000 a tonne in 2016 to more than $50,000 at the start of this year.

However, about two-thirds of the tin mined today comes from China, Myanmar and Indonesia, where there are long-running concerns about fragile supply chains and the use of child labour.

Don Turvey, the chief executive of Cornish Metals, said the US interest was “a testament to the quality and strategic importance of South Crofty and its potential to become the first new tin producer in the western world”.

Shares in Cornish Metals jumped nearly 7% on Thursday.

South Crofty received a £28.6m investment from the UK government in 2025 to support efforts to reopen it. Last summer, the chancellor, Rachel Reeves, estimated the mine the could support 1,300 jobs in the wider region.

Separately, a US-led critical minerals summit on Wednesday involving 50 countries produced a slew of agreements aimed at loosening China’s grip on more than 25 key elements, in their raw form and processed.

The EU and the US announced joint intentions to work closer together, committing to a memorandum of understanding in the next 30 days. The two will also work with Japan on building additional supplies, after a separate US-Japan arrangement signed in October.

The US state department said it had signed 11 bilateral deals on critical minerals at the summit, convened by the state secretary, Marco Rubio.

Patrick Schröder, a senior research fellow at Chatham House’s Environment and Society Centre, said speeches by Rubio and the US vice-president, JD Vance, had made it clear the driving interest was that the US wanted to secure supplies for AI development.

“Although they didn’t say it explicitly, it is still America first. It was framed as ‘America needs your help’. There was no mention of renewables,” Schröder said.