As French fishermen continue a blockade of the country's ports, there have been reports of confrontations, with stranded British sailors trying to escape.
Protest action has been continuing for more than two weeks
In protest against rising fuel prices, fishermen have prevented vessels from leaving, by blocking harbours with cables and large fishing trawlers.
British yachtsman Mark Leach said he and his boat had been stranded near Cherbourg since Saturday.
He told BBC News: "We tried to get out this morning, we were rammed by a French fishing boat.
"They pushed us into the harbour wall, then when we tried to follow a fishing boat which they allowed out, the fishing boat reversed and rammed back into us and damaged the front of our boat."
Mr Leach said a lighted flare had been thrown at him from the harbour wall.
"Luckily it missed the deck and landed in the water," he said.
Mr Leach said at one stage he fell into the water and a French fishing vessel tried to run into him.
"I was in the water and they tried to drown me."
Stranded on another boat, Paul Haysom, 60, from Lowestoft, Suffolk, said: "We've been sitting around here for seven days and been treated disgracefully. Flares have been fired and people intimidated."
The Foreign and Commonwealth Office (FCO) do not know exactly how many British vessels are affected by the strike, but reports from stranded sailors suggest several dozen could still be stuck in French ports.
The FCO said they believed 49 vessels had managed to sail free after the blockade was temporarily lifted on Monday night.
But an FCO spokesman added he did not know how many of these boats were British.
'Right to strike'
Also on board one of the stranded boats is Andrew Compton.
He told BBC News he and his crew had been stuck for four days, and that any attempt to escape had been blocked by fishing boats and a chain pulled across the harbour mouth.
Mr Compton said: "We seem to be kind of held hostage in a stand-off between the French authorities and a few quite militant French fishermen.
"We've got no hope at all unless the French police come and dismantle the blockade, which they have been entirely unwilling to do."
Neither, he said, had there been much assistance from the British consulate.
"The consulate in France said, 'Oh, they've got a right to strike and there's nothing we can do'".
Mr Compton said he, his crew, and many of the other Britons involved, should by now have been back at work following the bank holiday.
But one sailor, who had managed to take advantage of the temporary lifting of the blockade, said the experience had not been too gruelling.
Hugh Duncan, 58, a plumber from Lyme Regis, Dorset, said: "Last night between 1800 GMT and 2000 GMT they dropped the ropes.
"We all got out basically in a mass exodus of about 20 of us, mainly English sailors. There wasn't any violence used against us, or any need to take up any defence.
"We just left the harbour and sat outside it before leaving to return to England at 0500 GMT this morning. To be honest it wasn't a struggle to be stuck in Cherbourg because it's so nice.
"It was kind of annoying because we were just trying to do a wine run and it turned into this diabolical situation because of the French fishermen.
"But apart from that it was quite exciting and Cherbourg is not a bad place to be trapped."