UPDATE: The Associated Press is reporting Britain's national air traffic body, NATS, has fixed the computer problem. The body is in the process or reopening its airspace.
The agency says "we apologize for any delays and the inconvenience this may have caused."
Airspace over London has been effectively shut down due to a computer failure, according to various reports.
Travelers at five of the city's airports London Heathrow, Gatwick, Luton, Stansted and London City Airports — have been warned to expect severe delays.
Manchester Airport is the sole exception, remaining open and available for diverted flights from the capital, according to open and is poised to accept flights diverted from the capital, according to the news service FastFT.
NATS, the country's air traffic control service has issued the following bulletin:
"We apologise for any delays and our incident response team has been mobilised. Every possible action is being taken to assist in resolving the situation and to confirm the details. Further information will be released as it becomes available."
The shutdown couldn't have come at a worse time — the beginning of the weekend, a time when all five of the city's airports are typically bustling.
The Associated Press is reporting that a computer problem was responsible for the shutdown.
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