The Liberal Democrats have strongly backed a motion to extend the number of 20mph zones across the UK.
The vote, taken at their party conference in Brighton on Monday, is not binding on the Government but party members are hoping the proposals could soon become coalition policy.
The Lib Dems called on local authorities to consider introducing a 20mph limit in all residential neighbourhoods and other suitable roads, as well as backing the creation of a new ministerial post in the Department of Transport that would be given responsibility for implementing the policy.
The road safety charity Brake warmly welcomed the proposals and said that fast traffic was compromising the Olympic Games legacy of a healthier nation.
Julie Townsend, deputy chief executive at Brake, said: "There is a huge amount of enthusiasm at the moment for enabling people to live healthy, active lifestyles as a post-2012 legacy.
"We know fast traffic is a major barrier to this: many children, families and adults are prevented from walking, cycling and getting out and about because of the dangers."
Recent evidence suggests that recession-hit motorists have been slowing down anyway in 2012 in order to conserve fuel and avoid unnecessary bumps that could send theircar insurance premiums soaring.
Copyright Press Association 2012