One of Britain's largest unions has criticised plans to extend congestion charging across the country.
The scheme may be extended
The GMB said extending the scheme, which charges motorists £5 a day to drive into central London, would "penalise" those in areas without reliable public transport.
London mayor Ken Livingstone said the scheme was likely to be extended to other UK cities before 2005.
But GMB London regional organiser Paul Kenny said driving was the only way many Britons could get to work.
And the situation would not improve until every city had "an adequate and reliable integrated public transport network workers will want to use".
Only one out of every 10 people in Wales and Northern Ireland is currently using public transport, according to a survey.
Up to six out of every 10 London commuters are now taking buses, trains or tubes, it suggests.
But in England as a whole just one out of every seven people uses public transport, the survey indicates.
And in Scotland only one out of every six does, it suggests.
In Newcastle upon Tyne and Manchester just one out of every four people travels by public transport, according to the survey.
While in Birmingham only 22% of workers jump on the bus or train, it indicates.
The congestion charge for London was launched on 17 February and initial reports have shown around a 20% reduction in traffic in the zone.
Mr Livingstone said Mr Kenny's comments showed the capital did need the charge.
"Central London has one of the most dense networks of public transport in the world. At the same time, central London faced worst traffic congestion than any other city in Britain," he said.
"More than 80% of people travelling to work in central
London do so by public transport.
"That means there is a real and practical alternative to the car. Other
cities will obviously have to look at the situation on the roads and the
availability of public transport when considering the question of congestion charging."
A survey of 13 major retailers in Central London published on Tuesday has suggested the number of shoppers visiting the congestion-charge area has fallen nearly 5.5%.
Larger surveys of business are expected within the next month.