A technical problem has caused hours-long delays on British Airways flights on Monday evening.

Flights are continuing to take off but an IT issue affecting communications systems caused some flights to remain grounded. A spokesperson for the airline said: “Our flights are currently operating, but are experiencing delays as our teams work to resolve a technical issue affecting some of our systems.”

BA later said that they had resolved the issue, saying: “We’ve apologised to customers for delays to their flights and ensured they were able to reach their destinations as planned.”

A Heathrow spokesperson said: “The technical issue impacting British Airways has now been resolved. Our teams remain on hand to support British Airways to help passengers on their way as quickly as possible.”

Media reports earlier in the day suggested dozens of flights were unable to take off, with the travel journalist Simon Calder predicting cancellations into Tuesday morning.

He wrote on X: “British Airways IT system failure is causing delays of 1-2 hours on many BA flights this evening … As delays build up I fear there will be cancellations tonight/tomorrow.”

Earlier in the day, one traveller posted a photo of people queueing on the tarmac in Verona, Italy, commenting: “What has happened to the nations airline? Not fit for purpose.”

Another passenger posted: “BA 535 stuck on tarmac at Naples. Pilot hasn’t received load sheet and unable to communicate with Heathrow as internal phones are down.”

A second person wrote that the carrier’s app was not loading and showed a message that the page was in “high demand” while another posted: “Pilot said system is now fixed but there is a going to be big delay.

“He has suggested we will be sat on the plane for 1 hour before departure.”

Live departures on Heathrow’s website had showed delays of up to one hour and 25 minutes at Terminal 5.