The RIBA and fellow architects have hit out at continued royal interference in the planning process, as more evidence emerged this week of the extent of Prince Charles’ interference in Richard Rogers’ £1bn Chelsea Barracks development

As court documents showed the prince not only wrote to Qatari Diar owner, the emir of Qatar, but also lobbied him through his private secretary and during a personal meeting at Clarence House, architects lined up to say the affair was not a one-off event.

Ruth Reed, RIBA president, said: “It appears the Prince of Wales brought inappropriate pressure to bear on the democratic planning process. No individual should use their position in public life to influence a democratic process such as planning.”

Reed commented as the court proceedings began this week between Qatari Diar and Candy & Candy development vehicle CPC over the termination of the Rogers Stirk Harbour + Partners-designed scheme.

I think developers that show their plans to the prince are despicable

Piers Gough, CZWG

The documents showed the project was terminated after repeated attempts by the prince to derail it. CPC is claiming up to £81m for breach of contract, as the scheme was pulled just days before the planning application was due to be determined.

Jack Pringle, former RIBA president, said: “The prince’s actions are not compatible with a constitutional monarchy. It’s my understanding he regularly voices his opinions directly or through the Prince’s Foundation for the Built Environment. He’s in danger of operating as a second tier of planning permission, which is completely unconstitutional.”

Piers Gough, partner at CZWG, said: “Some developers show their plans to the prince to subdue him, and I think those that do are despicable. I like to think nobody would listen to him.”