Arrival will begin trials of its battery-electric bus with First Bus on public roads this autumn.
The new partnership comes seven months after First Bus announced its commitment to stop purchasing diesel buses after 2022 and to operate a fully zero-emission fleet by 2035.
First Bus already has electric buses in Leeds, Glasgow and York, a 99-strong fleet of biomethane buses in Bristol, and a hydrogen-powered double decker fleet in Aberdeen.
Arrival unveiled its electric bus, which it claims is up to 40% lighter than other battery-electric buses in the market, last June.
Avinash Rugoobur, president of Arrival, said: “Cities around the world are pledging their commitment to a zero-emission transportation future and Arrival is providing them with the ideal product to help them achieve that in the Arrival Bus.
"We are working in partnership with operators and cities globally to support improvements to public transportation networks whilst creating vehicles that can be tailored to local needs.”
Janette Bell, managing director of First Bus, said: “We’re proud to be the first operator in the UK to trial Arrival’s electric buses and look forward to working together to accelerate the transition to zero emissions in our sector."