All new buses ordered by Transport for London (TfL) for the capital will now be zero-emission.

The announcement, made as the UK prepares to host the COP26 climate change conference in Glasgow, follows on from TfL recently making its entire bus fleet compliant with strict Euro VI emission standards – the same standards as the Ultra Low Emission Zone.

Making buses zero-emission is estimated to save four million tonnes of carbon by 2037, and moving the date forward to 2030 will save an additional one million tonnes.

“In the year of COP26 and after setting out my ambition for London to be net zero by 2030, I’m committed to do all I can to help clean up the transport network and reduce its emissions,” said Mayor of London, Sadiq Khan.

“London’s toxic air is a shameful health crisis which is causing premature deaths and stunting the growth of children’s lungs.”

Road traffic, including cars and vans as well as buses, is the single biggest source of air pollution in the capital and accounts for around half of all emissions of harmful nitrogen oxides (NOx) and particulate matter (PM).