Ride-hailing giant Uber plans to charge customers in the capital city a clean air fee starting next year to encourage its drivers to upgrade to electric vehicles by 2025.

Uber's clean air act, a big step towards helping to tackle air pollution in London, provides a strong incentive for all cars on the app to be fully electric in London by 2025.

A 'clean air fee' of 15 pence (0.19 U.S. cents) per mile will be included on every trip booked through the Uber app in London, which means around 45 pence on an average trip, Uber said on its website.

Uber said the money will go towards helping drivers make the switch to electric vehicles as well as other clean air initiatives. Under the new scheme, a driver using the app for an average of 40 hours per week could expect around 3,000 pounds of support towards the purchase of an electric vehicle in two years and 4,500 pounds in three years.

Uber expects to raise more than 200 million pounds to support drivers transitioning to electric vehicles over the next few years, anticipating 20,000 drivers will upgrade to electric vehicles by the end of 2021.