Flights to everywhere from Belfast and Tenerife to Kraków, Poland, and Accra, Ghana, have been delayed by as much as an hour and a half this morning. Live arrivals boards also show slight delays to incoming flights. According to the monitoring website FlightStats, the delays are ‘excessive and increasing’.

Fog is continuing to disrupt flights at Gatwick Airport with restrictions imposed to maintain safety. On what is expected to be the airport's busiest day of the Christmas period, it said some flights "may be delayed throughout the day" due to "poor visibility" and apologised to customers.

Tens of thousands of passengers have had their Christmas travel disrupted in recent days as thick fog has descended on airports.