Hundreds of flights were cancelled or delayed across UK airports on Tuesday after a technical fault disrupted the National Air Traffic Services (NATS) flight processing system.

Axar.az reports, citing The Independent, that about 425 flights had been cancelled by 5 p.m., with Heathrow, Gatwick, Manchester and Birmingham among the worst affected.

NATS said engineers had identified and fixed the problem, but warned that restoring normal operations would take time. British Airways said it had cancelled or diverted more than 100 flights, affecting tens of thousands of passengers.

Passengers were advised to check with their airlines before travelling to airports. Transport Secretary Heidi Alexander said the government would seek assurances that lessons were learned from the disruption.