Hundreds of air passengers will have the misfortune of spending Christmas in hotels around Heathrow airport after British Airways cancelled flights due to fog.

The haze that caused travel misery over the weekend forced BA to axe dozens of Heathrow departures, causing misery for travellers who had hoped to be reunited with friends and families for Christmas Day.

"Most people have been rebooked or rerouted on other airlines, but some passengers will not be flying until the 26th of December," a BA official said.

The GMB union accused airlines of using the fog as an excuse for the situation.

"This time of year, if there is even a minor disruption, airlines and the handling companies that work for them are unable to cope because they run too many flights with too few staff. Simple as that," said the union's regional secretary, Ed Blissett.

Thirty flights were cancelled at Heathrow on Monday, while six were axed at Gatwick and six at London City airport.

Over the weekend, 90 departures and 112 arrivals were cancelled amid thick fog. Stranded passengers were forced to spend the night at Heathrow waiting for alternative flights, while others slept in nearby hotels.

On average, 1,250 flights arrive and depart from Heathrow each day. Despite the disruptions, many of the record 3.5 million jetting abroad this Christmas will have reached their destinations by Christmas Day - with Spain's Canary Islands the most popular.

Other favoured escapes for sun-seeking Britons are Egypt, Goa and Dubai. Those who have promised themselves snow have headed for the ski slopes of France, Italy and Austria.

Travellers face further disruption in January unless a compromise is reached to prevent a planned strike by workers at seven airports operated by the British Airports Authority including Heathrow, Gatwick and Stansted.

Two 24-hour strikes are planned - on January 7 and 14 - and a 48-hour stoppage is scheduled to start on January 17.

On the railways, around 240 passengers on a London-Scotland sleeper train run by ScotRail were stranded for several hours after their train hit "some material" on the track at Beattock Summit south of Carstairs in Scotland.

No one was hurt but the train, which had left London's Euston station at 8pm on Sunday, was damaged and locomotives had to be sent to get the train into Abington just north of the accident site.

ScotRail laid on coaches for passengers to Aberdeen, Inverness and Fort William. Elsewhere, problems with overhead power lines outside Paris delayed a Eurostar train from London for 59 minutes. Two other trains on the high-speed Channel tunnel route had minor delays.

Fog also caused problems on the roads, with a crash on the M4 spur at Heathrow, and accidents on the M69 in Warwickshire and the A38 in Staffordshire.

The Highways Agency has suspended many roadworks on England's motorways and major A-roads over the holidays, but works remained in place for safety reasons on busy routes including the M1 and M25.