Fresh plans to demolish a historic home on the edge of Hampstead Heath have been unveiled for the first time.

Although designs for Athlone House have been scaled back from earlier proposals with a smaller basement and no courtyard wings, campaigners insist it would still be a blot on the landscape.

The images – released for the first time – are the latest development in a planning row which has been raging between a foreign billionaire and neighbours for the more than a decade.

The 1870 pile, which served as a residence for several captains of industry and an RAF intelligence base and hospital, was snapped up a mystery owner in 2005 who plans to bulldoze the historic home and replace it with a larger house, featuring a ballroom, cinema, swimming pool and at least eight bedrooms.

Jeremy Wright from the Athlone House working group said: “The house has been there for 140 years and it has been designed to nestle into the landscape. These latest designs appear to have been made as a statement about the wealth and ambitions of the owner and is, in our view, highly intrusive into the land adjoining Kenwood House.”

Mr Wright claimed the plans still contravene planning guidelines because they ballooned beyond the footprint of the current house. Camden Council and a planning inspector rejected the last plans on this basis in 2009.

A spokesman from developers Athlone House Ltd claims the new designs have addressed the planning inspector’s concerns.

Gordon Maclean, of the Heath and Hampstead Society, said residents will “oppose this development” with their last breath and expected the society to make a “robust” response to the planning application once it has been lodged with the council for consideration.