A new dashboard gadget allows drivers to alert others when they have spotted a speed camera.

Drivers need simply press a button on the controversial GPS device and it will then transmit the location of the speedtrap to a processing centre.

The Mini Coyote from Novus is exploiting a loophole in the law, and can deliver the information in 3 seconds - which means that a car travelling 300 yards behind the driver who first spots the trap would receive the warning in time to slow down before the camera.

The device will display how fast you are going, the speed limit and the distance before you hit the camera as well as a warning as to how many times that specific camera has been reported.

But road safety groups are already stepping forward to criticise the device claiming that it will "undermine the ability of police to enforce the limit because drivers would be able to speed with very little risk of being caught".

The Mini Coyote is owned by more than 50,000 French drivers who reported 27,000 traps in September alone.

A spokesperson for the British Government has already come forward to warn that people using the Mini Coyote "could be prosecuted for perverting the course of justice”.

But Edmund King, president of the AA, said: "We think it would be extremely difficult to prosecute someone for perverting the course of justice if they had warned another motorist of speed cameras ahead".

Nigel Carter, from Novus, said: "This is actually a road-safety device because it will help prevent accidents caused by drivers stamping on the brakes when they spot a camera too late. As far as we can see, there is nothing illegal in the unit".