Parents could face a fine of £130 (€146) for driving their children to school as part of a plan to reduce air pollution.
The London borough of Croydon is the latest area to trial the scheme, which will see roads leading up to three primary schools becoming "pedestrian zones" for six months from September.
The zones will be car-free for between 90 minutes and two hours before and after every school day, reports the Evening Standard.
It is hoped the move will encourage parents to walk or cycle to school. Teachers, local residents and visitors to the school will be able to apply for special permits to avoid being charged for driving to the school.
A similar scheme to cut down on air pollution and improve road safety has already begun already trialled in Hackney, north east London.
The 'School Streets' initiative was launched at St John the Baptist C of E primary, Hoxton, and Tyssen Community Primary, Stamford Hill, in May. Any drivers caught parking in designated areas around these schools risked a fine of £130, reduced to £65 if the fine is paid within 14 days.
Stuart King, Croydon's cabinet member for transport and environment, said: "We're doing lots to make Croydon's roads less polluted, less congested and more pedestrian-friendly, and this 'school run' pilot is another way of achieving this.
"We want to make Croydon a healthier and safer place for all our residents, especially for youngsters, so I urge as many people as possible in these pilot areas to get out of their cars and walk their children to school."
London mayor Sadiq Khan has frequently spoken out about his worries regarding air pollution in the capital.
Khan has described the city's air as a "health crisis". It is estimated to cause the early deaths of more than 9,000 Londoners a year.
The mayor is planning on bringing in a toxicity charge for the oldest polluting vehicles in Central London from October and implementing changes that could see London's entire public transport system be zero-emission by 2050 in order to tackle the problem.