A DECADE-long saga over the fate of a Heath-side mansion is heading to the High Court after its mystery owners began judicial review proceedings against a block on their demolition plans.

The owners of Athlone House, in Hampstead Lane, lost a planning appeal over their attempts to knock the building down and replace it with a £80million mansion two months ago.

Conservationists and objectors hoped that decision would save the building but now they face going through it all again at the Royal Courts of Justice. A spokesman for the owners confirmed yesterday (Wednesday) that they felt they had strong grounds to have the appeal decision overturned. 

An original plan dating from 2004 approved by Camden Council set out proposals for luxury flats to be built in Athlone House’s grounds on the condition that the house was restored.

But after the flats were built, the owners went back to the Town Hall and asked for permission to demolish the house and build a luxury mansion boasting eight bedrooms, a ballroom and swimming pool in its place. The council has since issued an enforcement notice to the owners’ representatives demanding restoration work begins. Its stance was backed by an inspector at a planning appeal.

But now the to-and-fro looks set to be played out again in the High Court.

The Athlone House Working Group, made up of civic societies in the neighbourhood, has campaigned to have the owners honour the original agreement.  

Michael Hammerson, one of its members,  said: “The inspector’s decision was unequivocal. This is yet another unacceptable delay. We look forward to this being thrown out and substantial costs awarded against the owners. We can’t express our disgust in words at what we regard as an abuse of the planning system.”

A spokesman for the owners would not be drawn on what grounds they would be questioning the council  and inspector’s position, but added: “We believe there are strong grounds on which to challenge the inspector’s decision and that is why we are applying for a judicial review of the decision to refuse planning permission.”

Labour councillor Phil Jones, the Town Hall regeneration chief, said: “We have told the owners they have until July 29 to come up with their plans to restore Athlone House. We are confident of our legal position. 

“The inspector’s findings were compelling. The developer is adding insult to injury. They have been stringing this out for years and this is just another attempt to resist the requirements placed on them.”

No date has yet been set for the judicial review.