A court in southern France has backed a British couple’s 14-year legal battle to have a €57 million (£49m) chateau torn down after it was ruled illegal.

Nestling in green hills, olive groves and vineyards behind Grasse, France’s perfume capital, Chateau Diter has provided the glamorous backdrop for society weddings and the UK television drama Riviera.

This week, however, its businessman owner Patrick Diter was told he had just 18 months to tear down the Renaissance-style palazzo, after judges upheld an earlier ruling that the initial building permit had been obtained fraudulently in 2006.

All structures built since 2005 - including 3,000 square metres of accommodation, a heliport, a swimming pool and an approach road through a protected wood - must be removed, the court ruled. Only the 200 square metre original building can remain standing.

Failure to do so will see Diter face a €450,000 fine to be increased by €500 for every day he does not comply after the 18-month deadline.

At Diter’s trial in January, the assistant public prosecutor Pierre-Jean Gaury said the work he had carried out on the property was a “pharaonic project, delusional, totally illegal and built in an illegal manner”.

It had been built in violation of urban planning regulations as well as of safety and environmental rules by an owner whose “only concern is money”, he said.