In a landmark case, the Court of Appeal in London supported a property claim against a British couple made by a Greek Cypriot refugee.
Linda and David Orams, of Hove, Sussex, built a holiday home on land that Meletis Apostolides fled when Turkish troops invaded Cyprus in 1974, after a short-lived Greek Cypriot coup engineered by the military junta then ruling Greece.
The court ruled that Apostolides remains the rightful owner of the land, backing a November 2004 judgment by a court in southern Cyprus, where Greek Cypriots represent the island internationally.
The European Court of Justice (ECJ) last year also supported Apostolides's claim.
The ruling in London requires the Orams to comply with the original judgment in Nicosia, to demolish their home and return the land to Apostolides. They were also ordered to pay him damages and monthly rent until he regained his property.
"It's very disappointing," said Mrs Orams.
"Obviously it's a blow to us, but we're not going to let it ruin our lives. We're strong, we've dealt with this for over five years now."
She added: "The rulings will be a source of concern to many other property owners in (northern] Cyprus."
Apostolides, a British-trained architect, said he was "thrilled" by the ruling
It's estimated that some 1,400 Britons are living in homes built on property claimed by Greek Cypriot refugees.
But British and Greek Cypriot officials in Nicosia estimate there are up to 5,000 Britons living on land in the self-declared Turkish Cypriot state in northern Cyprus whose original title deeds are held by displaced Greek Cypriots.