The French fishermen's blockade was spreading last night, bringing more misery to thousands of cross-Channel passengers and wrecking holiday plans.

P&O Portsmouth, which had diverted Cherbourg-bound passengers to Le Havre, said it had been informed that Le Havre would now also be blockaded.

"The effect is that all P&O Portsmouth sailings to those two ports are suspended until the blockades are lifted," said a spokeswoman.

Meanwhile P&O Stena Line went to court in Boulogne to try to get an injunction to clear the port of Calais but a spokesman said it was "disappointed" with what the court had said so far.

It did not seem to want to link any injunction with fines for those who did not respect it - as had occurred in the past - but there were plans to raise the matter again today, he added.

Long queues of traffic built up at Dover and French ports because of the actions of the fishermen protesting over rising fuel prices.

Many ferry services were cancelled or diverted and some unfortunate holidaymakers had to sail back to the UK after being unable to dock at their French port.

The Freight Transport Association condemned the action, saying disruption at Calais alone was likely to cost British industry £1m a day.

A spokesman for Dover-based P&O Stena Line said after the court hearing in Boulogne last night: "The situation is a little unclear this evening. Our legal experts are seeking clarification and I think there will be more discussions with the court tomorrow.

"It appears ready to grant an injunction but does not seem willing to attach fines to it, which has been done in the past.

"At a rate of 2,000 francs an hour for people who do not obey the injunction, this has the effect of enforcing it and clearing a port of protestors.

"We are disappointed with the outcome today and hope that the situation will be settled to our satisfaction tomorrow."

The company was also raising its concerns with the French government through the British Embassy in Paris.

The action by the fishermen has affected the ports of Calais, Boulogne, Dunkirk, St Malo and Cherbourg. At one stage, police in Kent closed the M20 between junctions 11 and 12 allowing trucks to use the coast-bound carriageway as a huge temporary lorry park.

Companies affected by the strike included P&O Stena Line, Brittany Ferries, SeaFrance, Hoverspeed and Norfolk Line.

Sailings to and from Dover, Portsmouth, Plymouth and Folkestone were hit by the action.

One traveller stuck in Calais, David Langford, 28, from Norfolk, said: "I've just travelled from Thailand, passing through 11 countries, and it's always France that causes the trouble.

"I've travelled thousands of miles and it's typical that it all messes up when I am 23 miles from England."

Last night, there were rumours that the blockade could spread to affect Eurotunnel, but a spokeswoman said: "We have heard the rumours but have nothing definite on it."

So far its services have been unaffected.

The pressure on Dover and Calais was eased by P&O Stena's decision to operate extra passenger services between Dover and the Belgian port of Zeebrugge.

A Freight Transport Association spokesman said: "Once again British transport operators are extremely frustrated by the behaviour of French trade unions who take action without regard to the consequences for people abroad.