Lord West said it was “absolutely appropriate” for the government to prepare for the worst with the deployment of four extra patrol ships to intercept vessels in British waters next year.
However, the retired Chief of the Naval Staff suggested existing powers might not be enough, saying: “You can push vessels aside, you can cut their fishing tackle.
“But, actually boarding these foreign ships, they will need to pass a little thing through parliament to give authority to actually board and get on them.
“There is no doubt that, if you are a fisherman who has fished for years, they are – like our fishermen – quite stormy people and you get a bit of a punch up.”
But the Conservative chair of the Commons defence committee condemned the “absolutely irresponsible” sabre-rattling, as prospects for a Brexit agreement fade.
“Our adversaries must be really enjoying this blue-on-blue,” Mr Ellwood told BBC Radio 4.
“This isn’t Elizabethan times anymore. This is global Britain – we need to be raising the bar much, much higher than this.”
There are also huge doubts over whether the UK, even with extra patrols, has the power to police to 80,000 square nautical miles of British waters currently used by hundreds of EU fishing boats.
The 80-metre Navy vessels will be deployed after January 1, when the UK becomes “an independent coastal state”, to police up to 200 nautical miles from shore.
The move has echoes of the “cod wars” with Iceland in the 1970s, when Britain deployed 22 frigates to protect its fishing fleet. As recently as 2018 French and English fishing boats clashed over scallop fishing.
The risk of fresh clashes is growing after the EU proposed continued access to UK waters for a year, if the deadlocked trade talks in Brussels fail.
The idea was rejected by London but, on Friday, Emmanuel Macron, vowed France would not “give up my share” of fishing stocks.
The ‘XO’ committee, preparing for a no deal and led by Michael Gove, the Cabinet Office minister, is believed to have discussed plans for the Navy to intercept and board French boats if necessary.
One scenario included Royal Marines abseiling from helicopters onto vessels in the event of a “threat to life”, The Times reported.
Michel Barnier, the EU chief negotiator, and his UK counterpart David Frost have until only Sunday to somehow bridge the divide between the two sides.
Then, Boris Johnson and Ursula von der Leyen, the Commission president, will speak again – and pull stumps on the negotiations if they believe there is no prospect of them succeeding.
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