Some flights to and from the UK are facing delays and cancellations due to problems affecting French airspace.
British Airways said an air traffic control “outage” had hit flights going through French and Spanish airspace.
EasyJet said it was experiencing disruption due to a “partial failure of French air traffic control systems”.
Paris Airport tweeted that a “national computer failure related to the centralisation of flight plans” on Sunday morning was now resolved.
But it warned that delays were still expected.
National Air Traffic Services (NATS) said it does not know how many flights have been affected but it is working with airlines in the UK to try to minimise disruption.
Gatwick Airport said passengers should check with airlines on the status of their flights before heading to the airport.