The British government has ordered a review following the disruption of over 60 flights at London Heathrow Airport, the largest disruption to happen in a decade.

The National Air Traffic Services (NATS) experienced an outage on the final Monday in August, a public holiday in England, Wales, and Northern Ireland, which sees a high volume of travelers returning after the summer holidays.

Prime Minister Rishi Sunak told British broadcasters that he understood many would be "enormously frustrated".

According to Cirium, 790 flights and 785 arrivals were canceled at all UK airports on Monday.

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Thousands of passengers traveling to and from the United Kingdom are said to be stuck at airports after NATS revealed a technical problem with the flight planning system on Monday. NATS said the problem had been resolved by the afternoon, although delays and cancellations remained into Tuesday. Heathrow issued an amended statement, stating that schedules were still considerably affected.

The airport authority explained on social media that "due to yesterday's technical issues suffered by UK Air Traffic Control, there may be some continuing disruption on some routes, including flight cancellations."

Heathrow saw the most cancellations, followed by Gatwick and Manchester with many travelers stranded overseas. 

Mark Harper, UK Transport Secretary, apologized for the disturbance, calling it a technical fault rather than a cybersecurity incident. He warned that the effects would likely last for several days. He further denied that the outage was the result of hacking.

Harper told Sky News, "Our technical experts have looked at it and are clear that it was not a cyber security incident."

Harper remarked that the UK Civil Aviation Authority will look at ways to prevent such an issue from recurring since a technical problem of this magnitude has not happened for almost a decade.