This footage posted on You Tube shows planes grounded at Heathrow Airport due to the earlier system failure.
One Twitter user's weekend trip to Berlin has been delayed after he became stranded on the tarmac at Heathrow Airport.
Christmas weekend trip to Berlin off to a brilliant start stuck on the runway at Heathrow. Wunderbar
Luckily him and his friends are making the best of the situation.
At around 4.15pm Nats said the system had been restored and it was in the process of returning to normal operations.
"Following a technical failure at Swanwick, the system has been restored and we are in the process of returning to normal operations.
"We apologise for any delays and the inconvenience this may have caused.
"Further information will be released as it becomes available."
- Allowing some arrivals but departures are suspended
- Allowing arrivals, all departures delayed
- All departing flights currently suspended
London City Airport
- All incoming flights are landing, no departures until further notice
- Has confirmed flights affected but no more detail
Gatwick Airport said flights were landing but not departing due to the current outage in air traffic control in the London area.
A pilot and aerodynamics student, Brad Haverly, has tweeted that he is stuck on the taxiway at Gatwick Airport:
Stuck on plane due to closed London airspace. People growing increasingly agitated as we're stranded!! http://t.co/uUNuVMuuLX
Passengers across the country are grounded with some reportedly being asked to wait 12 hours to catch another flight. Others are not able to land.
@rupertevelyn yep - stuck on a plane at edinburgh airport trying to get back to Bristol. Think I'm missing the Christmas show!
Flight got cancelled and they are literally telling people to wait 12 hours for the next flight. Looks like I'm going to another airport
The delays caused by the temporary closure of London airspace appear to be spreading into northern Europe.
A map from Eurocontrol shows areas of northern France, Belgium, the Netherlands and Germany affected by delays.