CHRISTMAS travellers were enduring another day of airport chaos today with fog at London's Heathrow leading to hundreds of flight cancellations.

Those taking to the roads faced huge jams on major routes as others made their festive journeys on what is normally one of the busiest days of the year for traffic.

For the third day running, Heathrow is expected to be hit with more than 300 flights cancelled as air traffic controllers limit their services due to bad weather.

Around 50 aircraft should operate at Heathrow each hour, but safety procedures during low visibility cuts that to around 28.

British Airways axed all today's domestic services at Heathrow after cancelling 200 yesterday.

Long-haul services in and out of Heathrow will operate but some departing flights face delays.

By 8am Heathrow's second-busiest airline, bmi had already scrapped eight flights.

Airport operator BAA said it was providing amenities for stranded passengers, including blankets, sleeping mats, children's packs and food and drink.

BA laid on coaches for 3000 people to travel from Heathrow to Manchester, Newcastle, Glasgow, Edinburgh and Aberdeen.

The three-day disruption is likely to cost the UK economy at least £8million through lost productivity, experts say.

Meanwhile, the cold snap down south caused bookies William Hill to slash odds on a white Christmas from 16-1 to 8-1 in London.