London’s famous black cab fleet is set to become greener, with the city requiring all new cabs from 2020 to be electric vehicles, according to The Guardian.

The move, announced under a strategy to reduce the city’s air pollution, comes amid a gradual tightening of requirements on the cabs’ emissions.

Starting in 2012, the city will refuse licenses to any cab over 15 years old, Mayor Boris Johnson said, according to the paper. From the following year, the city will require semi-annual emissions inspections on each cab.

Black cabs contribute around 20 per cent of the city’s airborne pollution, according to The Guardian, with the city’s emissions among the worst of any European city.

London’s city hall has released figures showing long-term exposure to airborne pollution contributes to the premature death of around 4,267 Londoners each year.

Meanwhile, the green version of the black cab will be able to run for at least 100 miles on one charge of its lithiumion battery, The Sunday Times reports.

The move comes as the UK plans to install 4,000 electric vehicle charging stations across the country.