The cost of fuel is causing congestion levels on British motorways to fall at the same time as the overall number of cars on the road increases, according to green breakdown provider, the Environmental Transport Association (ETA).Recent increases in the cost of petrol and diesel have prompted a 12 per cent reduction in congestion on British motorways, and despite a slowdown in the number of new cars being sold the overall number of cars in Britain is increasing. Director at the Environmental Transport Association, Andrew Davis said: “Congestion might be down, but it is wrong to assume that it is simply because there is less traffic – when cars on motorways are driven carefully they not only produce less harmful emissions, they cause less congestion.”“The fact that the most impressive recent drop in congestion has been on a section of the M25 that does not yet have the highly effective variable speed limits that are in place elsewhere on the motorway, illustrates the gains to be made by a self-imposed careful driving style.”The ETA believes that increased fuel prices, revised rates of emissions-based vehicle excise duty and an increasing awareness of environmental issues is having an effect on our driving habits, but in the longer term, unless drivers ‘pay as they go’ reduced congestion on major roads will attract additional traffic.What is ‘careful driving’?Motorists can reduce their car’s emissions, the amount they spend on fuel and levels of congestion by taking the two following steps:Slow downReducing your speed from 70mph to 60mph will not dramatically add to your journey time but it reduces emissions and could save 20 per cent of your fuel bills.Do not tailgateDriving too close to the car in front is dangerous and inevitably causes a concertina effect which slows following traffic and can even bring it to a complete standstill.