Demonstrations started at 6am Monday (20 March) and are due to last until 6am Thursday (23 March). 

The strikes come after the French government passed a bill raising the national retirement age from 62 to 64 without a vote, causing the UK Foreign Office to update its travel advice to the country.

Air Traffic Control staff are reportedly joining the strike action and therefore air travel is likely to be impacted, easyJet said.

"We expect there will be delays and some disruption due to the industrial action, therefore we advise all customers to check the status of their flight on our flight tracker either on our mobile app or website," the airline added.

"Please also be aware that public transport services may be affected by the strike. We recommend all customers allow plenty of extra time to get to the airport and consider alternative transport options where possible.

"Although this situation is outside of our control, we would like to apologise to any affected passengers for the inconvenience caused."

Meanwhile, Ryanair said: "Due to a French Air Traffic Control strike, we are expecting possible cancellations or delays on flights to/from France on 20-23 March.

"Any affected passengers will be notified as soon as possible. We apologise for any inconvenience caused by this French Air Traffic Control strike, which is entirely out of Ryanair’s control."

Eurostar cancelled two services on Sunday (19 March) due to the strikes, but confirmed trains will run as normal on Monday (20 March) and Tuesday (21 March).