French air traffic controllers are threatening to strike for four days from today. In the UK, British Airlines cabin crew have voted overwhelmingly to take industrial action, and Germany's Lufthansa is now negotiating with pilots over a strike which affected tens of thousands of passengers.

From today, strikes by air traffic controllers in France are set to affect services all over the country. Civil aviation authorities will ask airlines to cancel some flights at Paris' two main airports, Orly and Charles de Gaulle.

Five unions are taking part. They are worried about how Europe's single sky policy will affect their jobs. The union's Len McCluskey says work conditions are also a major concern for unionised British Airways cabin crews, who have voted overwhelmingly to go on strike.

"A clear indication of the deep sense of grievance that our members feel," he said.

In the face of big losses, British Airways this year cut cabin crew numbers on long haul flights and brought in a two year pay freeze.

Mr McCluskey says the airline is threatening to take away staff travel perks if they strike, and bringing in strike breakers to pit workers against each other.

"These are people who fly together, these are people who put each other's health and safety in each other's hands, and to try to pit one against the other which the company has done and I have to say some pilots, not all, but a number of pilots have behaved in a way that I think when they look back on this in time to come when we have resolved this dispute, they'll be rather ashamed," he said.

However, analyst Howard Wheeldon, of BGC Partners, says British Airways has nothing left to give, and the striking crew will price themselves out of a job.

"We are not talking about the death knell for the airline, but we are talking about a situation in which the airline will be severely damaged and long term damaged, and it would lose out to its competitors," he said.

Mr Wheeldon says German airline Lufthansa is in a similar position. The company has just agreed to head back into talks with pilots, after a strike of less than 24 hours.

Lufthansa spokesman Klaus Walter says the airline has already been damaged

"We have passengers that are now cancelling their flights even if they have tickets for a later date and they could fly. They don't trust us anymore. The strike is also damaging our image," he said.

The pilots' union was planning a four day walkout, which Lufthansa says would have cost it 100 million euros.

The shorter strike was enough to disrupt the trips of 10,000 passengers.

"I just came back from Afghanistan and want to go to my family in the United States. It is difficult," said one affected traveller in Dusseldorf.

Lufthansa's 4,000 pilot strike has only been suspended for two weeks, putting extra pressure on talks.

French air traffic controllers will disrupt flights from today until Saturday, and British Airlines staff are legally required to give a weeks' notice of any strike action, meaning their strike could begin from the March 1.