Paris' public transport operator on Tuesday said it had ordered up to 800 electric buses to take to the streets of the French capital to replace diesel versions and fight smog in the build up to the 2024 Olympics.
Three French engineering firms - Heuliez Bus, Bollore and Alstom - won the tender to supply the buses in deals worth up to 400 million euros ($450 million), the RATP transport operator said.
RATP will buy an equal number of buses from each supplier, it added, describing the tender as the biggest such bus purchase in Europe.
It will begin by buying 150 buses, with the first deliveries expected between the end of 2020 and 2022, it added.
Local authorities in Paris want the French capital to have 100-percent clean buses by 2025 by using both electricity and biofuels.
"This is a major step for the RATP and a symbol of its ambition to be a key player in the energy transition in the public transport sector," said RATP chief executive Catherine Guillouard.
"To put them into service, the company is mobilised to meet an industrial challenge within a very short tight deadline," she added.
Paris already has one line - number 341 - fully operational with electric buses, but it will be a major task to transform its full fleet of just under 4,700 buses.
RATP currently has some 950 hybrid-powered buses, 140 bio-fuel buses and 83 electric buses in its fleet.
The use of electric buses is growing all over the world, with China the leader in employing the technology as it seeks to relieve pollution in clogged cities.
But they are becoming an increasingly familiar sight in European cities, in particular in Dutch cities Amsterdam and Rotterdam.
Paris' Socialist Mayor Anne Hidalgo has made tackling smog a priority and is planning stricter rules aimed at phasing out diesel cars by 2024, and is also weighing the idea of making public transport free.