A brewer today slammed a new European law which could force him to label his beer pumps with a warning that the bitter 'contains fish products'.

Steve Taylor, boss of the recently established Skipton Brewery, said the proposals being discussed in the European Parliament could threaten 500 years of tradition.

Isinglass, a fish product, has been used in the beer clarification process for centuries with no known case of an allergic reaction.

And Mr Taylor said the only alternative was to use artificial ingredients.

"This is a natural product that British brewers have used for 500 years," he said. "I don't think people would have sufficient knowledge to understand what this label means."

Timothy Kirkhope, Conservative MEP for Yorkshire and the Humber, said such a law could put some cask brewers out of business.

"A safe listing of allergenic products in ingredients is important to safeguard public health," he said. "But this is a step too far. There is no evidence that isinglass is detrimental to health."