Architects have called on Prince Charles to formally pledge not to interfere in the planning system

This follows a judge’s ruling last week that Qatari Diar had breached a contract by scrapping Richard Rogers’ £3bn redevelopment of the Chelsea Barracks site in west London.

The best thing he could do is graciously say he will only speak on general matters

Sunand Prasad

The calls come amid growing anger among architects at the decision to replace a modernist design by Richard Rogers, which the prince had criticised, with a more classical scheme.

Sunand Prasad, former RIBA president, said: “I would ask for a statement from the prince’s advisers promising the prince will desist from interfering with the details of individual planning applications.”

He added: “The best thing he could do is graciously say he will only speak out on general matters of principle and philosophy.

This would end his interfering with individual projects and the lobbying of the prince.”

Simon Allford, co-founder of Stirling prize-winning architect AHMM, agreed and added: “I would like the prince to clarify how the advice of his charities involved in the environment is not conflicted by his interest in vast estates. We need confidence the former are at best not compromised by and at worst not set up to support the latter.”

Not all architects joined the call for a pledge. Ken Shuttleworth, founder of Make, did not ask for any statement and added: “It’s down to clients to decide whether or not to take his advice, and lots do not.”

The comments come after Judge Geoffrey Vos made a ruling last week on Qatari Diar Real Estate Investment, the property arm of Qatar’s sovereign wealth fund. He said it had breached the terms of its contract with its former joint venture partner CPC Group, the developer controlled by property entrepreneur Christian Candy. CPC Group was claiming £81m in compensation after the Rogers scheme was abandoned.

Vos awarded CPC costs but said it was not entitled to early payment of £68.5m under the terms of the contract. However, he said he would consider the issue at a future hearing, should CPC seek damages.