A wealthy property developer has paid a powerful planning authority £180,000 to keep a basement swimming pool and gym which he built under his home in a conservation area without permission.

Ham & High: Marc Samuels's home in Hampstead Garden Suburb. Picture: Nigel Sutton.Marc Samuels's home in Hampstead Garden Suburb. Picture: Nigel Sutton. (Image: � Nigel Sutton email pictures@nigelsuttonphotography.com)

The Ham&High can reveal that the Hampstead Garden Suburb Trust dropped legal action forcing father-of-three Marc Samuels, 44, to fill in the basement at his Norrice Lea home.

The trust has confirmed in a statement that it had reached a financial agreement with Mr Samuels.

In 2012, Barnet Council and the trust, which rules on every development application in the Suburb conservation area alongside the council, granted Mr Samuels permission to build a one-storey basement under his home.

But during construction he extended the basement beyond the approved size, creating a 21m underground space beneath the home and stretching under the garden to accommodate a “cinema room”, “au pair’s room” and “pool room”.

He also added a second underground level housing a swimming pool and gym. In total, Mr Samuels created an additional 169sqm beyond what was permitted.

The trust, which has notoriously strict rules curbing changes to homes in the Suburb, consulted lawyers about obtaining a High Court injunction ordering Mr Samuels to reverse the unauthorised development, but claim they were advised to seek an out-of-court settlement due to “technical reasons”.

Last month, Barnet Council granted Mr Samuels permission for a retrospective application for the additional basement space.

Trust chairman Richard Wiseman said: “The trust is pleased to confirm that it has reached an accommodation with a resident who constructed a basement.

“The trust’s normal response to unauthorised development is to threaten an injunction and to proceed to obtain one either to prevent work taking place or to reverse it if it has already started.

“The trust can now announce that the matter has been settled for £180,000. This figure is based on the estimate of the enhanced value of the house, making appropriate allowance for the cost of construction and litigation risk.

“The resident has also made a contribution towards the trust’s legal fees. While the trust condemns the action of the resident, it acknowledges the spirit of co-operation with which he has dealt with the matter.”

Earlier this month, the trust issued new guidance to residents which effectively bans two-storey basements stretching beyond the footprint of a home.

Mr Samuels, who bought his home in 2007 for £2.9million, has spoken in the past about leaving school at the age of 15 to work as a labourer for a property investment company, and then setting up his own business.

He is also renowned for his philanthropy having donated to Hampstead Garden Suburb Synagogue and charity Chai Cancer Care. He was unavailable for comment.