CCTV cameras are to be used for the first time on some of Britain's most congested streets to catch motorists who break parking rules.

About 20 cameras have been set up in the heart of London to detect and fine owners of vehicles who park in restricted areas, such as on double yellow lines, or who cause an obstruction to other drivers.

They have been placed in some of the busiest streets in central London in an effort reduce congestion and keep traffic flowing.

It is hoped that the cameras will provide firm evidence of illegal parking and therefore reduce the number of tickets that are challenged.

They will also be used to spot and prosecute attacks on parking attendants.

For the next three weeks Westminster City Council is running an awareness campaign to inform drivers about its new high-tech parking enforcement.

During this time motorists who flout the regulations will not receive fines but will instead be issued with a warning. After this parking tickets will be issued automatically through the post.

The launch of the the CCTV cameras follows a successful t rial earlier this year throughout the City of Westminster.

The pilot showed an improvement in traffic flow due to a reduction in illegal parking.