Whitstable’s world famous oysters are among a number of British foods that could be under threat from Brexit, it is feared.

Former deputy prime minister, Nick Clegg, thinks that European rivals will start producing lookalikes to British foodstuffs.

Speaking at a food and drink conference, the ex-Liberal Democrat leader expressed his fear for homegrown foods if they lost legal protection offered by EU rules following Brexit.

Currently, Whitstable oysters have protected geographical indication status (PGI), which prevents manufacturers from outside the region copying the product.

Mr Clegg said: “Outside the EU they won’t enjoy the appellation bestowed on those products and I would have thought other countries would take advantage of that pretty quickly and put products into the European market that directly rival those protected brands.”

Whitstable’s oyster heritage has been documented since the Roman times.

James Green, of the Whitstable Oyster Fishery Company, says that the PGI status has often been ignored by other businesses.

“Whitstable oysters were one of the first products in the UK to achieve PGI status due to them being a well-known and respected product,” he said.

“However, that has not stopped people trying to pass off other oysters as Whitstable oysters.

“Only on Sunday, when I was in Margate, a shellfish stall there was selling their oysters as Whitstable when in fact they were from West Mersea.”

Despite the possibility of losing PGI status – which will increase the risk of lookalikes – Mr Green is confident it is Whitstable’s oysters that will remain the most desirable and well known.

He believes that no one can replicate their “unique flavour and superior quality”.

He added: “Our oysters have been world famous for more than 200 years and we believe they will remain desirable for another 200.”

Last week, the fishery used a new specialist oyster grading machine from France for the first time.