British AI infrastructure firm, Nscale, is in talks to secure a second $45bn (£33.5bn) computing deal with Anthropic, just a day after Microsoft pulled out of its flagship UK data centre project.

The Nvidia-backed company is negotiating an agreement to supply the US AI giant with computing power from a second facility at its Monarch campus in West Virginia. The proposed deal would cover 460 megawatts of capacity powered by Nvidia’s next-generation Vera Rubin chips, potentially doubling Anthropic’s Nscale commitments to almost $90bn.

The agreement could be signed within days, though discussions remain ongoing and terms could change, as reported by Bloomberg.

The talks follow an initial $44.6bn agreement signed in August, under which Anthropic agreed to lease computing capacity from the same West Virginia campus over six years.

The potential contract comes at a critical moment for London-founded Nscale, which is preparing for a blockbuster New York stock market listing amid growing scrutiny of the vast sums being spent on AI infrastructure.

The company reportedly targets a valuation of up to $30bn, although some investors have pushed for a lower figure between $16bn and $19bn.

Nscale and Anthropic have not commented on this deal.

Nscale faces mounting pressure ahead of IPO

The negotiations come just a day after Microsoft withdrew from plans to develop what was billed as Britain’s largest AI data centre in Loughton, Essex, dealing a blow to one of the UK’s flagship AI infrastructure projects.

The £2bn development, announced last year and championed by the government, has been delayed by issues with its electricity grid connection.

Nscale said it remained committed to the project despite Microsoft’s withdrawal.

“Our relationship with Microsoft remains strong and long-term, and this unfortunate London-wide grid issue has no impact on our other contracts”, a spokesperson said.

Microsoft also stressed that the decision related to a single site, adding that it remained committed to its wider partnership with Nscale.

The setback has raised questions about the company’s ability to deliver its ambitious data centre pipeline. Last week, Bloomberg reported that construction at Nscale’s flagship Norwegian facility in Glomfjord was six months behind schedule following technical problems, including cooling system leaks and a fire.

The company reported a $1bn net loss on $141m in revenue in the first half of 2026, while its IPO filings showed it had yet to secure financing for the infrastructure needed to fulfil its first Anthropic contract.

Under that agreement, Anthropic can terminate the deal if Nscale fails to meet certain financing and operational milestones.

The proposed second contract would therefore represent a significant vote of confidence in Nscale’s expansion plans, although the company would still need to secure funding for the additional computing infrastructure.

The talks also underscore the growing financial commitments underpinning the AI boom, as developers race to secure the computing power needed to train and run more advanced models.

Anthropic has struck several multibillion-dollar infrastructure agreements as demand for its Claude AI models grows, while investors have become increasingly concerned about the debt and execution risks facing data centre developers.