It said several unions had called for cross-sector strike action and demonstrations on Tuesday 7 and Saturday 11 February. Among those taking part will be air traffic controllers.

The FCDO warned: “Industrial action may start the evening before a strike day and run until the morning after. Localised or sector specific strikes could also occur outside these dates.”

A number of major airlines flying between the UK and Europe have taken action to guard against significant adverse effects on their schedules.

Ryanair

Ryanair confirmed it had cancelled “a small number” of flights, saying action would affect departures from 5pm this evening (6 February) until 6am on 8 February. 

Operations director Neal McMahon said: "We have had to cancel a small number of our 2,500 daily flights as a result of yet another pointless French ATC strike, the third already this year.”

McMahon continued: “Even passengers who are not flying to/from France are impacted because they overfly French airspace at a time when French laws protect French domestic flights. 

“Protecting overflights, as done in Italy and Greece is the simplest and most effective solution to avoid unnecessary mass disruption and must be implemented to protect passengers.”

EasyJet

EasyJet is also understood to have pre-emptively cancelled a small number of flights. "Like all airlines, our flights to and from France, as well as those flying in French airspace, could be affected.

"Also, flights that do not operate through France may still be affected, as 65% of easyJet flights operate through French air space and may be delayed before arriving for your flight.

"We expect that there could possibly be delays and cancellations due to the industrial action."

Jet2.com

Jet2.com said the action meant its flights operating to or through France "may be delayed". "If you’re affected, rest assured we’ll try to keep any disruption to a minimum," said the airline.

"Please arrive at the airport at least two hours before your departure time. Check-in closes 40 minutes before a flight’s scheduled departure time. If you are on a Jet2holiday, your transfer remains unaffected and will collect you at your scheduled collection time."

Revised Eurostar timetable

Eurostar, meanwhile, confirmed last week it was halting sales of Eurostar services departing London on Saturday 11 February ahead of half-term.

"There will be a strike in France on 7 and 8 February which will involve disruption across multiple sectors, including national rail services," said Eurostar.

"It will have an impact on the availability of some of our crew. This means, we’ll be running a revised timetable on 7 and 8 February."