LONDON 

Flights are gradually resuming across the UK following a significant air traffic control issue that led to widespread delays and cancellations at multiple airports on Wednesday.

The UK’s National Air Traffic Services (NATS) confirmed that a "technical issue" at its Swanwick air traffic control center in Southampton caused the disruption, temporarily halting departures from several major airports, including Gatwick, Liverpool, Newcastle, Edinburgh, Birmingham, and Luton.

In a statement earlier Wednesday, NATS said: "We are limiting the number of aircraft flying in the London control area in order to ensure safety."

The problem has since been resolved. However, delays and cancellations are continuing as airports and airlines work to return to normal operations.

As of 17:30 BST (1630GMT), 45 departures and 35 arrivals had been canceled across UK airports.

British Airways reported that the issue affected "the vast majority" of its flights. Passengers across all airlines are being advised to check directly with their carriers before heading to the airport.

Ryanair, one of Europe’s largest low-cost carriers, issued a strong statement in response to the disruption.

Neal McMahon, one of the airline’s top executives, called for the resignation of NATS CEO Martin Rolfe, stating: "It is outrageous that passengers are once again being hit with delays and disruption due to Martin Rolfe’s continued mismanagement of NATS."

He added: "Yet another ATC system failure has resulted in the closure of UK airspace, meaning thousands of passengers travel plans have been disrupted."

While the immediate crisis appears to be over, residual delays are expected to continue into the evening.

Passengers are urged to monitor updates from their airlines and airports closely.