Nearly 300 flights were cancelled on Tuesday because of a technical issue in the UK air traffic control system, the flight monitoring website Flightradar24 reported.Britain’s National Air Traffic Services said earlier on Tuesday afternoon that engineers were urgently working on the issue, which was affecting departing flights. In an update, it said it has “implemented a fix and our flight system is starting to recover”, and apologised for the disruptions.Flightradar24 reported on X that the problem affected dozens of flights operated by multiple airlines, including British Airways, EasyJet, KLM and Lufthansa.Heathrow, Stansted and City airports in London, as well as airports in Manchester, Birmingham, Scotland and elsewhere in the UK, said the technical issue was causing some disruptions. They warned passengers to check the status of their flight with their airline.Budget airline EasyJet said some of its flights were “unable to operate” and that the system failure caused “delays to flights across Europe”.Heathrow Airport’s website showed that many short-haul flights departing for European destinations on Tuesday were cancelled or delayed.Arriving flights did not appear to be affected. It was not immediately clear what caused the technical problem.