Britain has to protect its fishing industry, despite warnings stocks could be virtually wiped out by 2048, the UK fisheries minister has said.
A complete ban on cod fishing has been ruled out
Ben Bradshaw said the warning, issued by scientists on Thursday, represented the world's biggest environmental challenge after global warming.
But he ruled out a complete ban on cod fishing, saying a "zero catch" would see "the end of all fishing in the UK".
UK fishermen's representatives have criticised the report as "grandiose".
The international study, published in the American journal, Science, said supplies of fish such as cod were under threat from over-fishing and habitat destruction.
The government had already clamped down on illegal fishing and set fishing quotas "in line with the health of stocks", Mr Bradshaw said.
"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."
Measures taken in recent years had seen a 60% decrease in cod mortality rates, he said, which hopefully would continue.
Dr Nicola Beaumont from Plymouth Marine Laboratory was one of the scientists who helped draw up the report.
She said it was not just about fishing, but pollution, climate change, ocean acidification and destruction of marine habitats.
Greenpeace campaigner Willie Mackenzie said fish and chips would be off the menu "within our lifetime" if action was not taken now to tackle the problem.
"The good news in the report is that there is a solution. It proves that creating protected marine reserves, off-limits to industry and fishing, help fish populations to bounce back," he said.
But people working within the UK's fishing industry were sceptical about the report.
The chief executive of the Scottish Fishermen's Federation, Bertie Armstrong, said this was a "doomsday prediction" that ignored the steps being taken to address the problem.
Chris Sparks, from a Grimsby fish company called James and Son, said: "We don't believe this report at all.
"The industry's coming under increasing pressure, but there's still good stocks out there, well-managed stocks, which are managed by forward-thinking people, trying to keep up with the modern industry."
Doug Beveridge, of the National Federation of Fishermen's Organisations, said: "We have to be very careful about making grandiose, broad-brush predictions for 40 or 50 years and on a global scale also."
Fisheries and the marine environment could be managed regionally "on a collaborative basis with the fishing industry", he added.
Consumers have been urged to press restaurants and fish and chip shops to stock sustainable species.
And the British Retail Consortium said the UK's major supermarkets had increased their stocks of non-threatened fish, but this was a global problem.