A new type of speed cameras which use satellites to calculate average speed over extended distances are being tested. The cameras, which blend number plate reading technology with a global positioning satellite receiver, are similar to those used in roadworks. The AA said it believed the new system could cover a network of streets as opposed to a straight line.

The `SpeedSpike’ system, which calculates average speed between any two points in the network. The company said in its evidence that the cameras enabled “number plate capture in all weather conditions, 24 hours a day”. The system could be used for “main road enforcement for congestion reduction and speed enforcement”, and could help to “eliminate rat-runs” and cut speeds outside schools.

The development of speed cameras has raised concerns about expanding state surveillance. The AA said it would watch the procedure “carefully” but it did not believe there was anything menacing. “It is a natural evolution of the technology that is out there,” a spokesman said.