Shoppers should avoid haddock caught in the North Sea and West of Scotland fisheries as stocks fall below safe levels, the Marine Conservation Society said.

The fish, one of the UK's "big five" seafood species along with cod, tuna, salmon and prawns, is a favourite at the chip shop.

Haddock from three North Sea and west of Scotland fisheries are no longer on the charity's recommended "green" list of fish to eat.

However, the fishing industry has rejected the claims and moved to reassure chippy customers they can still order a haddock supper.

They have been downgraded because stock numbers in 2016 were below the recommended level and action was needed to increase the number of fish of breeding age, the society said.

Two of the fisheries are now rated "amber" - scoring four in a scale of one to five, where one is the most sustainable - in the Marine Conservation Society's (MCS) Good Fish Guide.

The other fishery has seen its fish drop from being a good choice of haddock to buy to one to eat only occasionally, with a "three" rating.

Bernadette Clarke, the MCS Good Fish Guide manager, said: "These ratings changes have come about because scientific perception of the stock has changed.

"Compared to 2015, the stock numbers in 2016 were below the recommended level and at the point where action is now needed to increase the number of fish of breeding age."

There is more positive news for some other fisheries, with scampi from Farn Deeps fishery being upgraded from the lowest rating of "five" - a fish to avoid - to a "four" thanks to better management, though it is still some way off being sustainable.

There are also improvements for scampi fisheries in the west of Scotland, Clyde and Jura catch areas in the latest list from the society.

Bertie Armstrong, chief executive of the Scottish Fishermen's Federation, hit back at the charity's claims.

He said: "The fishing industry is well used to these sorts of frankly meaningless publications - it's not so long ago that we were told that there were only 100 cod left in the North Sea. Try telling that to fishermen today who are seeing huge volumes of large cod on the grounds.

"Consumers can be re-assured that quotas for haddock have already been reduced in line with the stock assessments, following an unfortunate error by the scientists. So you can continue to buy your fish supper without worrying about whether there will be enough fish left in the sea."