Two millionaire neighbours are embroiled in a bitter courtroom battle over a bramble patch.

Retired businessman Neville Darby and David Bell, who was a chartered surveyor and company director, both claim ownership of the tiny plot, thought to be worth just £500.

The men, who own neighbouring £2 million mansions in 85 acres of land near the idyllic village of Cowden, near East Grinstead, have spent the past four years arguing and the dispute is now being settled with a £100,000 county court case.

Former Eastbourne College student Mr Bell, who moved to Cowden from Adelaide Crescent in Hove in 1991, claims squatters rights over the patch.

He says he has looked after the land, which includes an 18th Century cave, since he moved into the home and is claiming ownership under the 12-year squatters' rights law.

But Mr Darby, 67, argues the land has been allocated to his property since the 1700s.

He and his 63-year-old wife Kate are angry their plans to convert the patch have been delayed because of the dispute.

Mr and Mrs Darby live in a huge detached house called Furnace Mill, while their neighbour Mr Bell and his wife Diana, lives in the same road in a mansion called Furnace House.

Yesterday's hearing at Tunbridge Wells County Court heard from a man who was a friend of the previous owners of the two houses.

Frank Reader, who now lives in Horsted Keynes, said: "The man who lived at Furnace Mill was concerned about safety in the cave because children used to play there so he blocked it.

"There used to be a fisherman's car park there but its condition had deteriorated so the man who owned Furnace House had a gate made of oak built on the edge of the plot."

The battle over the bramble patch began in 1999 when Mr Bell phoned Mr Darby, an expert in local history, to ask if there were bats in the cave.

The former Fellow of the Royal Institute of Chartered Surveyors was inspired to take a keener interest in the cave and land. Mr Bell then erected a fence round the patch.

His actions infuriated Mr Darby, who ripped down the fence.

The two men have only spoken to each other twice since they became neighbours.

The hearing continues.