Switch will supply, operate and maintain the buses for the Bengaluru Metropolitan Transport Corporation under a 12-year contract. Switch said the 300 buses should reduce fossil-fuel consumption by around 5.5 million litres annually.

Competition in the electric bus market is heating up as countries, states and cities push towards zero-emission transport. Companies such as China's BYD Co Ltd and Volvo AB are vying with startups like California's Proterra Inc and Britain's Arrival

Ashok Leyland, India's largest bus maker, recently formed Switch, which includes parts of British bus maker Optare, to handle all of its global electrification efforts.

Switch buses are already on the roads in London. The company also plans to start production of a "global" electric van around 2024, joining a growing field of companies racing to bring zero-emission last-mile delivery vehicles to market.

(Reporting By Nick Carey; Editing by Pravin Char)