However, CTC highlighted the benefits of blanket implementation versus what it called the "patchwork" approach of 20mph zones.
CTC's Campaigns and Policy Director Roger Geffen said: "The adoption of 20mph as the default speed limit in urban and residential areas is the opportunity to redefine the spaces between our homes, changing them from 'roads' to 'streets'. With lower speeds, dangerous thoroughfares become public spaces where it’s easier to walk, cycle, socialise and play. People know more of their neighbours in low speed streets and property prices are higher, while 20mph is enough for vehicles to make progress."
He added: "Blanket 20mph beats a patchwork of zones: residents see a bigger return because more people buy in."
Many of the continental towns and cities where cycling is a popular mode of transport have 30 km/h speed limits, equivalent to 18.6mph.