Candy Brothers v the Duke in battle of Chelsea barracks

Britain's richest property owner is taking on London's most fashionable developers in a row over the transformation of Chelsea Barracks.

Gerald Grosvenor, Duke of Westminster, has objected to proposals by Christian and Nick Candy for the site, which was acquired last year from the Ministry of Defence for £1billion.

The Duke's Grosvenor Estate, which borders the site, has called the brothers' plans "monotonous" and "out of context".

Christian Candy's offshore company, CPC, with Qatari Diar, the development arm of Qatar's ruling family, is proposing 638 flats in buildings up to 13 storeys high, which would tower over the existing fabric of Belgravia.

Half the homes would be private flats designed by Lord Rogers facing Chelsea Bridge Road. On Westminster council's insistence, the other half would be "affordable" units. These will be designed by architects AHMM and will face Ebury Bridge Road.

The two sides will be separated by a "linear park", leading to complaints that the community will be segregated.

The plans, lodged with Westminster, were attacked by the Duke, whose Mayfair and Belgravia property empire is worth about £7 billion, in a letter to the council's chief planner, Rosemary McQueen, from Grosvenor Estate director Nigel Hughes.

He said the scheme was "right neither for the site, for the future occupiers, for the existing neighbours nor for the City of Westminster".

He added that while existing homes in the area were brick-built, pitched-roof houses of up to three storeys, the designs by Lord Rogers were typical of the industrial look he favours, mainly metal-clad and "more akin to office complexes". The buildings, and a proposed 108-room hotel and restaurant, were "monotonous, repetitive, totally out of scale and out of context", contrary to the council's brief.

Mr Hughes claimed the segregation of private and social housing went against the council's intention to create an inclusive community.

Locals have formed the Barracks Opposition Group. James Wright, chairman of Belgravia Residents Associationa member of BOG, endorsed the Grosvenor Estate report.

He said: "This site provided a rare chance to celebrate the best in a beautiful corner of this city. Instead, it looks like they're replacing one barracks with another.

"I am particularly appalled by the design of the social housing, which looks exactly like the slab blocks built by councils in the Sixties. Have we learned nothing since making those mistakes?" Other well-known names who have voiced their concerns and joined the objections over the plans include Roxy Music star Bryan Ferry, actor Rupert Everett and socialite Sir Dai Llewellyn.

The developers say their proposal is "a sensitively designed, mixed-use scheme of the highest architectural quality which "contributes to the local character and townscape with particular regard afforded to the adjacent conservation areas and listed buildings within the vicinity". A spokesman said: "We are sensitive to local stakeholders and meet regularly with local residents, including Grosvenor Estates and the Belgravia Association."

The Candys are behind some of London's most expensive properties, including One Hyde Park in Knightsbridge.