A number of potentially emission-free buses are being trialled in London, starting tomorrow (December 19th).

The two new vehicles have zero tailpipe emissions, helping to reduce overall pollutants across London.

Transport for London (TfL) has initially introduced these to commuter services between Victoria, Waterloo and London Bridge stations, as the technology is suited to shorter trips.

Senior environment and energy advisor to the mayor of London Matthew Pencharz said: "Electric buses could help deliver the cleaner and greener bus fleet we need to cut carbon emissions and improve air quality."

If successful, Mr Pencharz added the vehicles could be introduced in greater numbers alongside TfL's existing hybrid and hydrogen-fuelled buses already active.

Six additional buses have been secured and will start operating early next year. Four of these were obtained through the Green Bus Fund from the Department for Transport, with the other two funded through TfL's technology demonstration budget.

In the latest round of bidding earlier this year, TfL secured over £4 million from the Green Bus Fund for 90 vehicles.

Approximately 600 hybrid services are already in London and, by 2016, this will rise to around 1,700, or 20 per cent of the total bus fleet.