At least 10,000 British airline passengers have been grounded by the latest round of strikes by French air-traffic controllers.
British Airways has cancelled around 40 flights due to fly to, from or over France.
Six flights between Heathrow and Madrid have been axed, as well as four to and from Paris, Barcelona, Geneva and Rome.
BA said: “We will be using larger aircraft including some long-haul planes, where possible, to help affected customers and are doing all we can to reduce the levels of disruption.”
The long-running dispute between air-traffic controllers and the government is over job security, pensions and pay.
Ryanair has cancelled 12 flights to and from the UK, mostly affecting routes to Spain but also from Luton to Nimes and Stansted to Basel.
Meanwhile easyJet warned of widespread disruption: "We have been forced to cancel flights ahead of the strike.”
Late on Wednesday night it appeared that two of the air-traffic unions had reached an agreement with the government, but a settlement came too late to allow airlines to reshuffle their schedules.
Even with some controllers returning to work, Eurocontrol warns of severe delays, especially in western France - which has a severe impact on travellers between the UK and Spain. Airlines may cancel more flights over the weekend, which will disrupt travel plans for families heading home from the half-term holidays.
On the Channel, Brittany Ferries says that protests about labour reforms in France are disrupting its sailings this morning from both Poole and Portsmouth to Cherbourg; they are likely to be two hours late. P&O passengers between Dover and Calais have been experiencing cancellations and delays of nearly two hours, but the cause is poor weather rather than a blockade.
Rail passengers in France faced disruption for the second day, with around 60 per cent of long-distance trains likely to run, along with about one-third of local services. Yesterday the cancellations were exacerbated by long delays.
Francois Holland’s Socialist government is seeking to liberalise the labour market - which from the workers’ perspective means eroding long-held and hard-won rights, such as employment protection and the 35-hour working week.
A strike by transport workers in Paris appears to be having only limited effects. RATP, the public transport operator, says the Metro is running normally. On the RER suburban network, though, many trains are being cancelled - including more than half the links between Charles de Gaulle airport and central Paris.
