Uber has said that all taxis available through its app will be electric by 2040 - and by 2030 in US, Canadian and European cities.
The ride-hailing firm said the move was part of its "responsibility" to tackle the challenge of climate change.
The company said that it would spend $800m (£614m) to help drivers switch to electric cars, creating partnerships with manufacturers to ensure discounts.
Users will also be able to request an electric or hybrid vehicle.
That option is available in 15 US and Canadian cities for an extra $1, Uber said. It said it would launch in more than 65 cities globally by the end of the year.
"It's our responsibility as the largest mobility platform in the world to more aggressively tackle the challenge of climate change," chief executive Dara Khosrowshahi said in a blog post on Tuesday.
"While we're not the first to set ambitious goals in transitioning to [electric vehicles], we intend to be the first to make it happen."
Climate change contributors
Uber and smaller rival Lyft have faced ongoing criticism for their role contributing to traffic and air pollution, with research showing many of their rides replace less polluting alternatives, like walking, biking, or taking public transport.
Lyft in June pledged to have an all electric fleet by 2030, but it did not outline support for drivers. Many of them operate their own cars.
Uber on Tuesday said that battery electric vehicles accounted for roughly 0.15% of the miles logged on its platform in the US and Canada between 2017 and 2019. Including hybrids, the mileage logged in green vehicles is about five times the average in the United States.
In London, where it has clashed with regulators, Uber had already pledged that all the firm's rides would happen in electric cars by 2025.
- EU says one in eight deaths is linked to pollution
- London Uber fares go up after electric car charge
- Coronavirus: Uber announces drastic cuts to secure its future
- Uber and Lyft drivers are employees, says US judge
On Tuesday, Uber said it was working with Renault and Nissan to expand that effort to other European cities, starting in France. In the US and Canada, it is working with General Motors.
Uber said drivers will earn more per ride if they are using electric or hybrid cars and it was also working to include more alternatives to cars in its app.
Climate change organisations, which have pressed the company to improve its environmental record, said they were pleased by Uber's announcement.
"Uber's commitment to rapidly electrify its fleet in major European cities is good news," said William Todts, executive director of the campaign group Transport & Environment.
"Now it's time for Europe's city mayors to show leadership. We need all big cities in Europe to introduce zero-emission zones, new pop-up bike lanes and cycle-only corridors, while also providing easy access to charging at home, at work and wherever people park."