Thick fog, road and rail accidents and strikes in the UK and France have been causing major delays for travellers.

Motorists from Devon as far north as County Durham have been urged to take care driving in patchy fog on Monday, which has reduced visibility 50 metres in some areas.

The derailment of a train outside Ealing, west London, on Sunday has also led to a restricted service between Paddington and Reading.

As the firefighters' strike enters its fourth day 23 London Underground stations remain closed.

Some flights have been grounded by the threat of a French air controllers' strike.

But fears that a French lorry drivers' dispute would lead to blockades at French ports, causing further travel chaos, have so far proved unfounded.

Fatal fog

British lorry drivers and travellers have been able to move freely across the Channel.

A spokesman from the BBC's Travel News said there had been a number of accidents on motorways and trunk roads across England.

One person died in an accident on the M40 near Gerrards Cross, Buckinghamshire, which has caused delays.

The ports are clear despite the French lorry drivers' dispute

Parts of Scotland have also been blanketed by fog.

A BBC Travel News spokesman said flights from major airports had not been affected by the weather but there were delays on flights from Guernsey, in the Channel Islands, to the UK and France.

Mist, fog and low cloud will again be slow to clear on Tuesday morning and the firefighters' strike could last until Saturday.

The French lorry drivers' dispute started on Sunday but a spokeswoman for Dover-Calais ferry operator P&0 Ferries said: "It's very much business as usual, and the strikers seem to be leaving the ports alone."

UK Freight Transport Association spokesman, Geoff Dossetter, said: "Eurotunnel car and freight shuttle services are working well and there are no queues at Dover."

There were further reports that police had ordered strikers to remove blockades that had been set up on French roads.

Air travel is also being hit when French air traffic controllers begin a planned 34-hour walk-out later on Monday, forcing the main UK carriers to cancel or reschedule flights.

British Airways is grounding a total of 62 flights to and from Gatwick and Heathrow just before and during the 34-hour controllers' strike over pay.

A further 12 return services operated by BA's CitiExpress from UK regional airports have also been cancelled.

Budget carrier Go is rescheduling its flights to Nice and Lyon, and Ryanair and easyJet said they were monitoring the situation and poised to make changes if necessary.

Budget airline Buzz announced the cancellation of nearly all flights to and from France.