Cheating Spanish trawlers operating out of Wales have been blamed for helping to put up the price of fish and chips across Britain.

Swansea Crown Court handed down the biggest fine ever seen in Wales after a judge was told that blatant overfishing by the Spanish was partly responsible for a massive 40% cut in next year's fishing quotas.

The cut has led to warnings that the price of fish and chips will rocket to £4 by next month.

Anglo Spanish Fisheries were fined £102,000 after its trawler the Gaztelutarrak was caught for the fourth time.

Prosecuting, Geraint Walters claimed the Spanish - who operate Europe's biggest fishing fleet - were practising "deceit on the high seas".

He said the skipper of the Gaztelutarrak, Manuel Villas, used a layer of boxes containing cheap fish to conceal the real cargo - more than a ton of megrim, a type of flat fish.

More worrying, he said, was that the skipper coded the top boxes so the port workers in northern Spain would know the valuable fish were underneath.

Sea Fisheries officers boarded the Gaztelutarrak when she tied up in Milford Haven before heading back to Spain.

Judge Christopher Morton said: "Fishing stocks are under threat.

"These offences were deliberate and the only inference is that they were to avoid quota restrictions."

The company admitted five offences involving the accurate recording of catches.