Sir Keir Starmer has been urged to “seek assurances” amid concerns that hundreds of jobs in the heart of the Red Wall could be at risk from a priority shift away from the UK.

Mining firm Anglo American’s recent merger with Canadian company Teck is heightening fears of job losses at the Woodsmith project in Yorkshire.

With 1,100 Britons employed at the site, Tees Valley Mayor Ben Houchen is leading calls for reassurances about the future of the project.

Speaking to GB News, the top Tory said: “The slowdown at Woodsmith has already put hundreds of Teesside jobs on hold and created real uncertainty for families and businesses who were relying on this project.

“Anglo American promised a transformational investment, with the materials handling facility and export terminal at the heart of Teesside’s economic future.

“Instead, we’ve seen spending slashed, timelines pushed back, and confidence undermined.

“With Anglo now pursuing a merger with Teck, the concern locally is that Teesside could be deprioritised.

“We need Anglo to confirm it is prioritising this project as part of the takeover, confirm it will not be defunded and deprioritised and that they immediately put forward a fully-fledged plan that ensures this region will see the jobs, skills, and long-term investment we were promised.”

Despite Mr Houchen’s growing fears, Anglo American has sought to quell concerns about an impact on jobs, instead declaring that its merger with Teck will not affect the Woodsmith development.

The deep underground project, which is set to be Britain’s biggest new mine in decades, was acquired in 2020 when Anglo bought Sirius Minerals, the former AIM-listed company behind the scheme.

Earlier this year, Anglo American said that work on the mine will not resume until 2027 at the earliest.

However, a leading levelling up advocate, who previously served as an adviser in No10, called on Sir Keir to intervene on the matter.

In a damning intervention, they told GB News: “The Government is asleep at the wheel when it comes to business.

“It is a sad state of affairs that one of our largest companies has decided to saddle up alongside Mark Carney in Canada, deprioritising the UK in the process.

“This has real world consequences for the levelling up agenda that this Labour Government has done so well to destroy.

“The Government should immediately seek assurances from Anglo that their UK operations will not be further affected and jobs will be protected.”

Around 1,000 people previously working on the project have already been laid off, leaving about 1,100 still employed.

Mined polyhalite from Anglo American’s Woodsmith mine is transported via a 23-mile tunnel, known as the Mineral Transport System, that connects the mine near Sneatonthorpe to the Wilton International complex on Teesside.

Construction on the tunnel began in April 2019 and about three-quarters of the track has been completed so far.

Capital investment in the mine has been cut from $3billion over three years to far lower levels, dipping near zero in later years.

Anglo maintains there has been progress on the multibillion-pound project, despite spending reductions.

“Anglo Teck will continue to progress the development of the Woodsmith project in the UK with its ongoing potential to be a generational asset in crop nutrients,” the company said.

“Full development remains subject to meeting stringent investment criteria for risk-adjusted value, including syndication to one or more investment/strategic partners.”

While Anglo and Teck say they are committed to the mine, concerns are growing that the companies are yet to put forward a full plan for how they intend to safeguard Woodsmith’s future.

Responding to fresh concerns, a spokesman for Anglo American said: “We will continue to progress the development of the world-class Woodsmith project in North Yorkshire with its ongoing potential to be a generational asset in crop nutrients, working towards completing the shaft sinking and full design phase, ahead of syndication and board approval in a few years’ time.

“Full development remains subject to meeting stringent investment criteria for risk-adjusted value, including syndication to one or more investment/strategic partners.”

A Government spokesman added: “We are pleased that London will remain the base for Anglo Teck’s incorporation, tax and primary listing, showing that the UK continues to be an attractive place for investment and it is positive the company has committed to progress the development of the Woodsmith Project.

“Through our Plan for Change, the UK continues to be an attractive place for investment, having been ranked as the best in the world following our recent deal with the US.”