Fog is expected to cause further disruption to flights at some of the UK’s busiest airports.

Passengers at Gatwick have been warned to expect possible delays on Saturday because of poor visibility and are advised to contact their airline for updated information.

Stansted Airport is also experiencing some disruption.

Thick fog patches could reduce visibility to just 100 metres in some areas across the country, the Met Office said.

A spokesperson for the Gatwick said: “Temporary air traffic restrictions have been put in place due to fog causing poor visibility.

“Some flights may be delayed throughout the day.

“London Gatwick apologises for any inconvenience. Passengers should contact their airline for further information.”

Flights were delayed by up to three hours from Gatwick on Friday evening because of poor conditions.

Sunday is expected to be the airport’s busiest day during the holiday period, with 769 flights planned.

Heathrow Airport passengers are also advised to check with their airlines regarding any potential delays, a spokesperson said.

Nats, the UK’s main air traffic control provider, said on Saturday temporary air restrictions would remain in place in areas with low visibility.

A spokesperson added: “Restrictions of this sort are only ever applied to maintain safety.

“We continue to monitor the situation and have a Met Office expert embedded within our operation to ensure we have the latest available information.

“Our teams are working closely with the airports and airlines to minimise disruption.”

Passengers for flights delayed more than two hours may be entitled to assistance with providing food and drink or overnight accommodation if necessary, an expert from consumer website Which? said.

Jo Rhodes, Which? travel expert, said: “If your flight is cancelled, you also have the choice of being refunded or rerouted on the next available flight.

“If you choose the latter, then your airline must get you to your destination as soon as possible – including with a rival carrier, if necessary.

“Airlines can sometimes be reluctant to buy you a ticket with their competitors, so don’t be afraid to remind them of this rule if another flight could get you where you need to go quicker than they can.”

The Met Office advised travellers to allow “a little bit longer” for journeys and warned drivers to leave extra braking distances in areas with poor visibility.

Saturday is expected to be “dull” and “rather cold” with highs of 10C in Scotland and Northern Ireland, and a maximum of 8C or 9C elsewhere, according to the weather service.

Some rain will fall in Scotland and Northern Ireland followed by “brighter weather” and potentially sunshine later in the afternoon, the forecaster added.

Met Office senior forecaster Craig Snell said: “For a lot of us, it’s another grey, murky day and some poor visibilities around.

“Tonight, we should start to see a little bit more in the way of breeze developing, so that should start to disperse some of the poorer visibilities across the rest of the UK.

“So we might start to see some of the fog and low cloud begin to lift as the night goes on, but generally with plenty of cloud around, but not really expecting any issues with frost or anything like that.”

South-east England is expected to see a “dull” start to Sunday but overall, it will be a “brighter day” with highs of 12C predicted, he added.

Towards New Year’s Eve, the weather will become “unsettled”, with wet and windy conditions forecast across the north of the UK and “less expansive” rain forecast in the south.

The Met Office has issued a yellow warning for snow and rain for most of Scotland next week and said heavy downpours could bring “significant disruption” in the build-up to Hogmanay.

Rain and snow warnings are in place for much of Scotland on December 30 and 31 apart from Orkney and Shetland.

According to the forecaster, 50-70mm of rain is possible over the two days in many areas, while some places may see 100-140mm – with these higher totals most likely over western Scotland.

Snow is possible in northern Scotland and over high ground, while strong winds could bring further disruption, particularly on New Year’s Eve.

A yellow weather warning for wind in northern England on Monday has also been issued – with gusts of up to 60mph possible which may cause travel delays and power cuts.

The warning, in place from 11am to 6pm, covers areas including Durham, Northumberland, Cumbria and North Yorkshire.