London Mayor Sadiq Khan has backed the use of new 20mph zones, saying they save lives and, contrary to popular belief, "don't slow traffic".

Lower speed limits play a crucial role in the Mayor's Vision Zero plan to eliminate deaths and serious injuries on London's transport network by 2021.

Since 2018, Transport for London has introduced more than 264km of 20mph speed limits, with over half of the capital's roads having a lower speed limit.

Research from Transport for London shows that 20mph speed limits have resulted in a 34 per cent drop in the number of people killed or seriously injured on roads across the capital.

Sadiq Khan has called for more 20mph speed limit roads to be rolled out in the interests of road safety

There has also been a 40 per cent drop in the number of people killed on roads that have been converted to 20mph.

Sadiq Khan is now calling on other local authorities, councils and the national Government to introduce more 20mph speed limits.

He cited the 20mph speed limit rules introduced in Wales three years ago, noting that 100 fewer people were killed or seriously injured in the first year of operation.

The controversial driving laws meant that all restricted and residential roads would be transformed into a 20mph speed limit to boost road safety.

Sadiq Khan has backed projects that improve road safety and cut emissions

Despite criticism from motorists over claims that it was slowing down journeys, data showed that the slower limits were helping reduce the number of accidents, injuries and deaths on roads.

Many called for the 20mph speed limit to apply only to certain roads where it was applicable, including near hospitals, schools and nurseries.

Sadiq Khan said TfL would roll out 20mph speed limits on "appropriate roads", adding that the development of "school streets" had accelerated in recent years, with more than 800 across the capital.

The number of protected cycle routes has also increased fivefold, with Khan noting that this would give the confidence to "swap four wheels for two".

He told the Guardian: "Roads where 20mph speed limits apply aren't just safer; they are quieter, too, encouraging more people to walk or cycle. Those who do drive have fewer collisions and pay less for their insurance as a result.

"It's no surprise that residents overwhelmingly back slower speed limits in their own communities; more than three out of four of them think that 20mph is the right speed for the area they live in."

Khan also referred to the success of the Ultra Low Emission Zone (Ulez), which is the first of its kind anywhere and the largest in the world.

The zone was expanded to cover Greater London and contributed to a 27 per cent decline in roadside nitrogen dioxide levels.

The Mayor's Vision Zero scheme aims to reduce the number of fatalities and serious injuries to zero by 2041

Over the last six years, air quality at monitoring sites across the capital has improved by a staggering 99 per cent.

Khan, who has been Mayor of London since 2016, claimed that boroughs had "leapt at the chance to make our roads safer", with 21 having a default 20mph speed limit.

He reiterated these calls on social media site X, formerly known as Twitter, saying "the evidence is clear" and "we need to see more 20mph areas".

Former Transport Secretary Louise Haigh said that local authorities were best placed to decide where 20mph roads should be installed.