There have been more calls for drivers to be charged to use UK roads.
A pay-as-you-go road scheme is needed to guarantee funds and limit traffic growth, according to Professor Glaister, director of the RAC Foundation.
Despite the coalition government claiming that road pricing may only be introduced on new roads, a number of people have called for a scheme for existing roads in order to avoid traffic gridlock and provide funding.
Similar ideas have also been put forward by Tim Yeo, Chair of Energy and Climate Change Select Committee, who claims road pricing needs to be introduced to help 'decarbonise our transport system' as well as transferring roads to private ownership to help raise extra cash.
The plans put forward by Mr Yeo are for drivers to pay depending on their cars' CO2 emissions so that owners of the biggest, most polluting cars will pay more while charges will also be increased during rush hour periods to cut down on traffic.
Another suggestion is the use of 'carbon credits'. Under this plan every driver gets a certain amount of carbon credits to use and once they have been used up they then have to buy more credits from other drivers.
According to Mr Yeo this charging could also help pay for a cut in fuel duty meaning that those who don't use motorways on a regular basis will also benefit from the charging.
In a recent poll on Parker's 43% of people asked said that they felt some kind of road charging was a good idea.