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Portsmouth has become Britain's first '20mph city' by introducing a blanket 20mph (32km/h) across its south-east section.
The move follows a government child road safety strategy report published in February, which suggested that local authorities and the Highways Agency should consider wider use of 20mph zones and traffic calming measures in areas where children used roads.
One pressure group in particular, Brake, is campaigning for compulsory 20mph zones in residential areas and around schools for the whole country.
Cathy Keeler, head of campaigns for Brake, described the 20mph limit as "level headed" and those who opposed it as "speed freaks".
Of 7000 pedestrians killed or seriously injured on roads around Britain, 2000 are children aged under 15.
