Currently, drivers who have personal use of vans pay tax based on a standard £500 charge.
But in the pre-Budget statement, Chancellor of the Exchequer Gordon Brown announ, ced he was pushing ahead with research on a new van tax regime, revealed in last year's Budget.
The statement said: 'Budget 2002 announced that the Government would review the tax treatment of the private use of vans provided by employers, taking into account environmental benefits, fairness and modern working practices. The Government will discuss with industry and other key stakeholders how best to achieve this, with a view to launching a formal consultation next year.
'The Government will consult in particular on how to simplify the legislation for shared vans and on the scope for encouraging environmentally-friendly vans.'
Already from next year, the Government has announced a reduction in Vehicle Excise Duty for vans that meet stringent Euro IV emissions standards, but there are fears that taxing drivers according to their van's emissions would prove unfair.
Stewart Whyte, director of the Association of Car Fleet Operators, said: 'Unlike car-based taxation, van drivers have little choice of which vehicle they use. Whether you drive a large or small van depends on the company you work for and what the van is required for. It is an absolute tool of the trade, so why should drivers have to pay tax at different rates?'
Peter Howard, head of fleet supply at BT Fleet, which operates more than 30,000 vans, said: 'It is very early days for us, but this is a very important issue because of the scale of our van fleet.'
David Butler, director of Dyer and Butler, which operates 70 vans, said: 'At the moment, there is not much administration for us. It is really straightforward. I can't honestly see how this is going to work.'