The strike could cost British Rail up to pounds 10m in lost revenue and coincides with industrial action by London bus drivers locked in a pay dispute, and a miners' stoppage over pit closures.
Yesterday, the Prime Minister attacked the rail strike as 'deplorable', but Jimmy Knapp, general secretary of the National Union of Rail Maritime and Transport Workers, said his members were 'angry and concerned' about losing their jobs and would solidly support the action.
Steven Norris, Minister for Transport in London, advised people facing serious travel problems to stay at home, but the London Chamber of Commerce said that its members would be expecting most employees to 'struggle in'.
Special parking in the capital has been allocated for coaches but normal parking restrictions will be enforced, particularly on main traffic arteries. Police and motoring organisations appealed to car drivers to avoid adding to traffic congestion by staggering journeys and taking passengers.
The AA predicted 'traffic bedlam'. London, which attracts 400,000 commuters using BR trains every day, is expected to be worst hit. Last night the AA reported heavier than usual traffic leaving London, suggesting many commuters had heeded warnings and started the weekend early.
The strike called by the 68,000-strong RMT threatens to wipe out the 15,000 train journeys run by BR on a Friday. Almost 3,000 engineering workers employed by BR voted yesterday to join the stoppage. Paul Watkinson, BR personnel director, urged Mr Knapp in a letter to call off the 'damaging' action, adding that the BR board could not 'ever' give an absolute guarantee of no compulsory redundancies.
Leaders of RMT maintained that BR had been happy to provide assurances of no compulsory job losses in 1984 but had refused to consider the issue in peace talks on Wednesday. Further stoppages would be considered after a review of today's action.
Mr Knapp said that 7,000 jobs were to be lost this year, including 2,000 from regional railways, 1,500 from InterCity and 1,400 from Network SouthEast. 'It is not a jobs-for-life argument. We have asked BR not to use contractors on traditional railway work when railworkers are being made redundant,' he said.
The London Chamber of Commerce said it was concerned that a minister should be advising people to stay at home during the strike 'given the state of the economy'. A spokeswoman said: 'With all the rationalisation that is taking place in the City, people can't afford the luxury of taking time off.'
Midland Bank has laid on a fleet of 63 coaches to ferry staff to its main London branches and Lloyds Bank is spending pounds 50,000 to bus in London staff. Arrangements were made for judges to stay at the Old Bailey so that 16 of the 19 courts will sit today. Gatwick airport, normally served by a high-speed rail link, is laying on extra coaches between London's Victoria station and the airport.
BR said that all efforts would be made to return the service to normal as quickly as possible tomorrow, while season tickets would be extended by 24 hours.
In London, a strike by 7,000 bus drivers over pay cuts and longer working hours will add to travel problems. Twenty Underground stations which share lines with BR close are also expected to be closed.
Arthur Scargill, president of the National Union of Mineworkers, appealed to other trade unionists to take action today to support the coal industry and the union's campaign to save all 31 pits originally scheduled for closure.