Plans to build a 147MW data center in Slough, London, have been further delayed after developer Tritax Big Box announced yesterday that a decision on planning permission would be postponed by three months.

The fate of the data center was set to be decided yesterday by the UK Ministry of Housing, Communities, and Local Government.

But Tritax has issued a press release and a bourse filing saying that a decision was expected on or before June 9, according to the government.

A reason for this delay was not provided.

In early 2025, developer Manor Farm Propco – an affiliate of Tritax – applied for planning permission to build a data center campus at the 74-acre Manor Farm, a part-greenfield and part-brownfield site located at Poyle Road that it owns.

Although Slough’s local authority has been broadly welcoming to data centers in the past – the area is home to the largest concentration of data centers in Europe – it argued that Tritax’s proposal should be rejected because of the parcel’s ‘Green Belt’ designation.

If a land is considered ‘Green Belt,’ it is protected from certain kinds of development.

Slough Borough Council also argued that there were suitable alternative sites in the nearby Slough Trading Estate that Manor Farm Propco had not considered, and that Heathrow Airport might use Manor Farm as a freight forwarding facility in the future.

Sensing that Slough Borough Council was likely to reject the proposal, Manor Farm Propco appealed the case to the UK’s Planning Inspectorate in April before the council could reach a decision.

The appeal was accepted before being “called in” by the Secretary of State for Housing, Communities, and Local Government, Steve Reed, giving Reed the power to make a final decision.

A public inquiry, in which both sides presented arguments to an official from the Planning Inspectorate, was held in October.

The UK government’s bullishness on data centers has made it eager to support projects in spite of opposition from local authorities and residents.

In December 2024, former Secretary Angela Rayner overturned a local council’s rejection to greenlight a 140MW development at the Court Lane Industrial Estate in Buckinghamshire. In 2025, Rayner did the same with projects in Abbots Langley, Hertfordshire, and Buckinghamshire.

Current Secretary Reed has been following in Rayner’s footsteps, and his decision to ‘call in’ a 4MW data center proposal on the site of the historic Truman Brewery in London’s Brick Lane has sparked intense backlash from local residents and politicians.

But the government’s strategy was dealt a heavy blow in January after it admitted that it had made a “serious logical error” when granting planning permission to a data center in Buckinghamshire, making it likely that the decision will be quashed.

Manor Farm Propco is a company set up by real estate investment trust Tritax Big Box, which is also behind a proposal to build an 88MW campus in Chelmsford, Essex.