Those heading the campaign want the Government to introduce metric measurements before the Olympic Games in 2012.
However, in a manifesto published this week, the UK Metric Association says it would cost £80 million to switch the UK’s 200,000 road signs from miles to kilometres.
In the manifesto Lord Kinnock states: "Imperial road signs contradict the image and the reality of our country as a modern, multicultural, dynamic place where the past is valued and respected and the future approached with creativity and confidence."
Paul Watters, head of roads and transport policy at the AA Motoring Trust, believes a change in the current system could have faults. He said: "A key flaw lies with speedometers that primarily measure miles per hour. Any precipitous change over will create confusion, danger and anger."