The White Ensign of the patrol vessel HMS Blazer was burnt after she was surrounded by eight trawlers in the harbour at Cherbourg, where she was on a goodwill visit. French fishermen boarded from a jetty and the seven crew and nine civilians on board retreated below decks for three hours.
Earlier, three Royal Navy fishery protection men were held after challenging a French fishing boat in British waters.
David Curry, the fisheries minister, told BBC radio last night that Royal Navy boarding parties may be instructed to use a 'higher degree of force' in future incidents. 'They are not out on a Sunday boating trip and if they are going to receive this sort of provocation, then the next time the French are going to meet with something just a little bit more severe.'
The Foreign Office said the French authorities had brought the Blazer incident to an end last night and the trawlermen had left the vessel. 'We are grateful to the French in bringing this regrettable episode to a conclusion,' a spokesman said.
The three abducted fishery protection men where among five from the minesweeper HMS Brocklesby who boarded the Calypso, a French boat suspected of illegal fishing off Alderney.
The French skipper ignored orders to head for St Peter Port in Guernsey and set out for French waters with the three, including at least one officer, on board. Two had left earlier by boat. 'Our people didn't want to go to French territorial waters but they ended up going there in the course of their duties,' a Ministry of Defence spokesman said.
Brocklesby shadowed Calypso as far as French waters but the British captain decided not to use force to stop the boat. The three returned to Brocklesby in a French port vessel after Calypso had reached Cherbourg.
British diplomats in Paris will raise the two incidents with the French Ministry of Marine today. A French patrol boat, the Coriander, is to be stationed in Cherbourg today.
French and British trawlers fished in Channel Islands waters until last September when the EC recognised a six-mile British limit.