Forty years on it looks as though Theresa May has taken a leaf out of Ted Heath’s Book of Betrayal in her treatment of British fishing. In his rush to get into the Common Market, Ted betrayed fishing by accepting a Common Fisheries Policy cobbled together just before our entry negotiations by the six existing members to get access to the rich fishing grounds off Norway and Britain.

The CFP required “equal access to a common resource”. We contributed two thirds of the fish stocks to that common resource but were graciously given only a third of our own fish back. That meant a massive run down in our fishing industry. It eliminated any prospect of rebuilding it within our own waters as every other fishing nation was able to do when the UN accepted that fishing limits should be extended to 200 miles.

Under the CFP, English fishing got a meagre six-mile limit which was regularly infringed. “North Britain” – which didn’t include the North East or Yorkshire – got 12 miles, resulting in disaster for the English industry and damage to the Scots.

Brussels decided who could catch what in our waters and tried to keep everyone happy by handing out paper fish. Policing was a nightmare. French trawlers occasionally trawled right up to the Yorkshire coast, destroying British lobster pots. Beam trawlers damaged our grounds. I found on a fishery protection vessel that while British vessels were assiduously policed, foreign vessels breaking the rules could simply nip over the median line to escape prosecution.

Finally, to add insult to industry, the EU court decided in the Factortame case that European fishing companies could hop the quotas by taking over British companies and catching their British quota too. Indeed, chairing a fishing committee visit to Spain I was introduced to the Chairman of the Fleetwood vessel owners. He spoke little English.

This farce should end with Brexit. The CFP isn’t based on either the Single Market or the Customs Union, though “fishery products” are. Yet now the CFP is to be extended over the transition period so catches will continue to be determined by Brussels until 2020. After that, Michel Barnier’s deputy, Sabine Weyand, has announced the UK will “have to swallow a link between access to products and fisheries”, meaning unless we continue the CFP, they’ll keep out our fish exports.

That’s unacceptable. It means continuous control over fishing, more disputes like the battle between British and French vessels and no rebuilding of British fishing. We can be sure that at the end of a transition period in which we have no say and no negotiating weapons, Spain, France, Denmark and Holland – which depend on their British catches – will fight to keep them. Even that’s assuming the EU ever allows us to end the transition.

That means little control of our own waters. It means no year-by-year gradual reduction in EU catches, no stock swaps with nations like Norway which control their own stocks. Crucially it will deter investment in rebuilding our British industry to fish in our own, once rich, waters. Who’s going to put money into fishing without the certainty that British fishermen will get sustainable catching of our own fish?