The news will come as no surprise to observers, coming after the government's recent confession that it will fail to reduce CO 2emissions by the planned 20 per cent within four years.
Back in November the AJ revealed that Mayor Ken Livingstone would not come close to his ambition of building at least one zero-carbon development in each of London's 33 boroughs by 2010.
Today's revelations follow the demise of a £6 million 'revolving fund' for investment in renewables and energy efficiency - a victim of the growing Olympics cash drain.
As a result of questioning from Darren Johnson, Green Party member of the London Assembly, the Mayor acknowledged the 20 per cent drop in emissions was no longer possible.
Johnson said: 'Climate change is among the most urgent issues facing both London and the planet. It's a serious failing for this target to be abandoned only two years after it was set. This seriously undermines the Mayor's claim to be at the forefront of tackling climate change.
'Instead of dropping the target, London should be leading international efforts to reduce carbon emissions - through a major drive for energy efficiency, investment in small-scale renewable energy, and further action to reduce traffic.'
London's target of a 20 per cent reduction in carbon dioxide emissions from 1990 levels by 2010 was set out in the Mayor's Energy Strategy, published in 2004.