Technical problems with the national air traffic control system is affecting flights in or out of London Luton Airport.
But passengers are advised to check in for their flights as normal.
The national air traffic service (NATS) is experiencing technical problems at their Swanwick control centre and to maintain safety is restricting the number of aircraft flying across the south of England and those taking off from airports
This has not resulted in the closure of UK airspace or the suspension of all flights in or out the UK.
In a statement NATS said: “We regret any inconvenience this may cause however our first priority will always be the safety of the flying public.
“NATS is taking every step to restore services and has contingency plans in place to minimise any disruption.