BBCNews.com: The London mayor's office says it wants to have 100,000 electric vehicles on the road by 2020.
London's mayor has only achieved 3% of his target of having 100,000 electric vehicles in the city, it has emerged.
In 2009, Boris Johnson pledged to meet the target "as soon as possible" but there are currently about 3,000 such vehicles on the road in the city.
The mayor also wanted 25,000 charging points across London by 2015 but only 1,408 are in operation today.
In response, his office said it was on target to have 100,000 electric vehicles in use in the capital by 2020.
Sunday Politics London reporter Andrew Cryan said: "London should be an ideal place for electric vehicles to pick up as they don't have to pay the congestion charge and the journeys tend to be quite short so you don't have to worry about running out of battery.
"But so far the pick-up hasn't been great."
In January 2009, there were an estimated 1,700 electric cars in London.
The mayor's Electric Vehicle Delivery Plan pledged to make London the electric car capital of Europe by improving infrastructure, having 1,000 electric vehicles in the Greater London Authority fleet by 2015 and encouraging the take-up of car clubs.
Out of its fleet of about 8,000 buses, just two are electric and the battery life means they can only be used on relatively short routes and are not strong enough to drive a double-decker.
Transport for London also says all new taxis must be zero emissions capable by 2018.
Stephen Knight, Lib Dem member of the London Assembly, said only 57% of the charging points were used in the first three months of this year.
He said the money should have been spent elsewhere.
"Investing in electric vehicles that the mayor can influence - the taxis, the minicabs, the buses - then that would provide the stimulus for everybody else to follow," he said.
Isabelle Dedring, the deputy mayor for transport, said: "We've always thought that around 2020 might be the mark when that's achievable (having 100,000 electric vehicles) and that's in line with industry expectations as well.
"Our experience has been people are not wanting to charge at trickle posts (charging points).
"Instead, what we're bringing in is support for people to charge at home but we're also putting in a rapid charging network, which is much more like going to the petrol station."
