The main suspected cause is electricity supply. According to the Telegraph, national grid officials told Nscale they did not expect to provide power to the site until the 2030s. Nscale's Norway flagship is also behind schedule, with only 6.4 megawatts of its intended 30-megawatt capacity running. Earlier reporting linked Loughton to a government-backed project, and one outlet describes ministers calling it the largest UK sovereign AI datacentre. That claim rests on a single source and has not been independently verified. The Telegraph report has not been confirmed by either company, and the terms of the terminated agreement are not public.
The timing is significant because Nscale is preparing a US IPO that could raise as much as $3 billion as soon as this month. Its IPO filing states that Microsoft and Anthropic account for roughly 85% of contracts, so the loss of Microsoft heightens concentration risk, and the Loughton site now has no publicly announced customer. Watch for amended IPO filings, which should clarify the termination's financial impact and the company's revised customer picture. Microsoft's reported pullback from other UK and international sites, as reported by Bloomberg in 2025, suggests this may not be an isolated decision.