In addition, the world’s first hydrogen bus is to be trialled on the capital’s roads next year as part of plans to make all buses meet the Ultra-Low Emission Zone standard during 2020.
It is estimated that the equivalent of 9,400 premature deaths occur each year in London due to illnesses caused by long-term exposure to air pollution, with diesel vehicles recognised as a major contributor.
Khan said: “I want London to become a world leader in hydrogen and electric bus technology. I’m implementing hard-hitting measures to clean-up London’s toxic air.
“Transforming London’s bus fleet by accelerating the introduction of zero-emission buses is important and I plan to work with bus manufacturers, other cities, the European Commission and the C40 Climate Change Leadership Group of Cities (C40) to move this agenda forward.”
Worldwide, 3 million deaths each year are linked to exposure to outdoor air pollution according to the World Health Organisation, with the vast majority of these deaths occurring in cities.
Since Khan’s announcement, mayors from Paris, Mexico city, Madrid and Athens have pledged to remove all diesel vehicles from their roads by 2050.
The commitment was made today at the C40 Mayors Summit in Mexico City in an effort to improve air quality for their citizens.
Mayor of Paris, Anne Hidalgo, said: “Mayors have already stood up to say that climate change is one of the greatest challenges we face.
“Today, we also stand up to say we no longer tolerate air pollution and the health problems and deaths it causes – particularly for our most vulnerable citizens.
“Big problems like air pollution require bold action, and we call on car and bus manufacturers to join us.”
Obstacles to using greener buses include the higher up-front capital and infrastructure costs involved.
The C40 has announced it will host a finance academy in April to help cities unlock funding for more zero-emission buses and the supporting infrastructure required to address this problem.
EU transport commissioner, Violeta Bulc, said: “I congratulate the cities of London and Paris on their far-reaching plans to deploy clean buses.
“European cities are global frontrunners, and I encourage all cities to make use of European funding opportunities to support this transition.
“Better co-operation of public authorities, operators, manufacturers and finance is needed now.
“Therefore, we are developing a deployment initiative for clean buses at a European level, including a platform to better align planning and investment.”
New York, Los Angeles, San Francisco, Amsterdam, Copenhagen and Cape Town have all since agreed to begin moves to phase out their procurement of pure diesel buses by the end of 2020.