Drivers could pay up to £1.34 a mile in "pay-as-you go" road charges under new government plans.
Every vehicle would have a black box to allow a satellite system to track their journey, with prices starting from as little as 2p per mile in rural areas.
Concerns that the tracking system would lead to the state knowing where people were all the time, would have to be addressed, said Mr Darling.
"It will mean taking some stick. There are a lot of difficult decisions to be taken," he said.
A pilot scheme could be carried out using volunteer drivers in a large British conurbation within five to six years, but a national scheme would be rolled out within 10-15 years.
The Environment Agency's Nick Rijke warned that shifting money away from fuel duty would take away the incentive for people to use green vehicles.
BBC News
£5000.00 p.a. road tax, anyone? Er...anyone? Helloooo - where have you all gone? At least there's nothing on the roads anymore so we've cured congestion.......now, what can we tax to make up for the fall in fuel duties?
Please click on the link below to let these idiots know what we think of them...
http://petitions.pm.gov.uk/traveltax