The Mayor of London Boris Johnson has unveiled his new plans to make London the ultra-low emission vehicle capital of Europe, which include lowering the congestion charge further for low-emission vehicles and giving grants to taxi drivers to encourage them to switch to electric cars.

The plan sets out a series of goals that hope to encourage the use and increase the numbers of ultra-low emission vehicles (ULEV) in the city.

The ULEV delivery plan lays out a number of schemes and areas of exploration, including improving the congestion charge discount for ULEVs, increasing the number of electric vehicle charging points, and giving decommissioning grants to taxis that are more than 10 years old, in an effort to encourage drivers to take up zero emission vehicles.

The plans could even lead to the introduction of preferential access and lower parking charges for ULEV vehicles in some parts of London. The Mayor's Office has said it will "explore" this idea, and will work with London's boroughs to develop it.

The Mayor's announcement came as the London Fire Brigade announced that 57 of their support vehicles will be replaced with hybrid electric cars by next year. The Brigade is also looking into the adoption of low emission fire engines, calling on industry to bring forward new technologies that can meet their demands.

London's New Routemaster buses are already hybrids, and Transport for London (TfL) is looking to make the bus fleet greener, through introducing more electric buses and new electric-only routes.

London is the most polluted place in the country, with air toxicity levels in some areas reaching up to three-and-a-half times the EU legal limit. A recent study by TfL and the Greater London Authority found that 9,500 Londoners died early in 2010 because of pollution.

Buyers of electric cars, like the G-Wiz, are already given incentives by the city, such as exemption from the congestion charge (Oli Scarff/Getty Images)

Due to pollution's severe health impact on London's residents, the British Lung Foundation welcomed the new plans to cut emissions.

Dr Penny Woods, Chief Executive of the Foundation, said: "After the shocking air pollution mortality figures published last week for London, it is right and necessary that measures be put in place to bring down these emissions in the capital."