The Mayor of London, Boris Johnson, has outlined a plan to remove the western extension of the London congestion charge.

The move is intended to encourage the use of carbon efficient cars and ensure that the environmental benefits of the congestion charge are being maintained.

The mayor has proposed a green vehicle discount for cars emitting 100g/km of CO2 or less and meeting the Euro V standard for air quality.

However, Transport for London (Tfl), the local government body responsible for most of Greater London’s transport system implementation, said it thought the proposal will cause a £55m ($80m) loss in revenue and would lead to an increase in congestion and air pollutants in the area.

Tfl suggested using measures such as accelerated installation of computer-optimised traffic signals and utilising the London roadworks permit scheme to minimise congestion problems.