The UK government plans to tax vehicles not used on the road, according to an independent watchdog.

The Association of British drivers said a consultation document recently issued by the licensing authority, the DVLA, details plans to introduce a new tax on all cars registered on its system, even those that are not used on the road by their owners.

The "Fee Proposals" consultation, which closes on 8 November, claims the new tax is necessary to cover the costs of issuing photo licences to all drivers, as required by the European Union.

An annual fee of £4.50 is proposed on all vehicles kept on the DVLA's computer. For most cars used on the road, this extra tax will be collected with the vehicle excise duty (formerly called road tax).

However, it will also apply to disabled drivers, pre-1973 classics and cars kept off road under the SORN (Statutory off Road Notification) regulations. None of these categories currently pay VED, so this will be an entirely new and separate tax.

"This means that people are going to have to pay tax to keep their own vehicles in their own garage," said ABD spokesman Nigel Humphries. "£4.50 a year may not sound much, in fact it hardly seems worth the DVLA's trouble to collect it where this cannot be done through VED. But it's a dangerous precedent, and a matter of principle. Why should we pay anything for the details of our property merely to be held on someone's computer?"

Enthusiasts often have several cars kept off road - future projects, possible parts cars, "saved" cars they hope to pass on to others to restore - and they will have to write out and send off a separate cheque for each vehicle every year, as the off-the-road anniversary of registration arises. The DVLA will then have to bank them. That's a lot of trouble and expense for nothing, and how much will the DVLA have left of the money after it has administered this bureaucratic leviathan on behalf of one hapless individual?

"And who is to say that the fee will remain at £4.50?" added Humphries. "The government has a long history of introducing taxes at low levels and then increasing them year on year, and people are reluctant to trust their assurances. This new registration tax gives them a mechanism for abolishing VED, adding the cost of this to fuel tax and then increasing the registration fee, automatically wiping out the benefits enjoyed by ultra low mileage classic car owners and disabled drivers alike, as well as creating a punitive charge for those storing cars off road. That is why it is to be resisted."

The ABD is calling on the DVLA to see sense and desist from penalising classic car owners, disabled drivers and car collectors with this "pointless and bureaucratic" system.

"Motorists pay £36 billion a year to the government in motoring related taxes. If the European Union wants photo licences there is plenty here to pay for it," the organisation said.