Owners hoping to knock down Athlone House and replace it with a palatial home overlooking Hampstead Heath will have to take their fight higher up after Camden Council rejected the planning application.

A bid to replace historic Athlone House in Highgate with an eight-bedroom luxury home was rejected by councillors during yesterday evening’s Development Control Committee meeting, with some describing the proposals as “Stalinist” and “grotesque”.

More than 5,000 people formally objected to the plans in what is thought to be a record-smashing number.

But yesterday’s decision has not been welcomed by campaigners as an outright victory.

Planning officers recommended that committee members refuse planning permission but a legal bid to get plans approved by the Planning Inspectorate has already been lodged by developers.

The protection of the building from demolition is also still uncertain.

Most objectors had signed a petition calling for the mysterious owner to honour a historic agreement to restore it to its former glory.

The agreement required Athlone House to be renovated within 42 months of work starting on the construction of flats in Caenwood Court.

As the deadline for renovation works to the house approached, an application to demolish and rebuild the property was submitted.

Until the current application has been resolved, the council says, it is unable to take enforcement action on the previous agreement.

Politicians, community groups, international visitors and those living nearer to home – including Monty Python actor Terry Gilliam – have all condemned the proposed demolition of the former RAF base and hospital on the edge of Hampstead Heath in Highgate.

Also among the complainants are the great-great-granddaughter of the house’s original builder, the superintendant of Hampstead Heath, the grandaughter of one of the mansion’s last occupiers, national conservation group English Heritage, Hornsey and Wood Green MP Lynne Featherstone and Camden Council’s finance chief Cllr Theo Blackwell.

A spokesman for Athlone House Limited said: “We remain absolutely committed to building a house of the highest quality on this important site.”

For more on this story, see the next edition of the Ham&High (out August 7).