He told BBC online that the situation represented the world's biggest environmental challenge after global warming but added that a ban would signal "the end of all fishing in the UK".

The increasing scarcity of fish and seafood species could also lead to the disappearance of entire ecosystems, according to the report published by United States and Canadian researchers in the journal Science.

Commenting after publication of the report, Bradshaw said that the UK had already taken action by clamping down on illegal fishing and setting fishing quotas.

"If there were to be a zero catch for cod, we would have to close almost all of the UK fishing industry because there's almost no part of our fishing industry that doesn't catch some cod as by-catch," he told the BBC.

Britain has the fourth highest cod catch levels in Europe, after Spain, Denmark and France, according to official figures.

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