Instead he will concentrate on "fully-funded schemes that we know can be delivered".

The schemes that have been dropped include a £1.3bn cross-river tram plan, a £500m Thames Gateway Bridge scheme in east London, and a £750m extension of the Docklands Light Railway to Dagenham Dock.

A £500m Oxford Street tram scheme has also been scrapped as well as a £170m Croydon Tramlink extension and public space proposals for a number of areas including Parliament Square and the Victoria Embankment.

News of the cancelled schemes came as Johnson launched Transport for London's (TfL) 10-year business plan.

He said the plan contained "multi-billion pound" projects and would create thousands of jobs.

The programme includes bringing back the routemaster bus, upgrading the tube network and building the £16bn Crossrail underground link between Heathrow airport and east London.

The London Mayor has also pledged to deliver transport projects for when London hosts the Olympics in 2012.

Boris Johnson said: "London is the engine of the UK economy and it is vital that we continue to invest in better transport during these tough times. But at the same time, we need to focus on the projects that deliver real benefits for Londoners, and let go of those that lack the funding for completion.

"These projects still required a total of over £3bn in funding from the Government or other sources. At a time when Londoners are struggling it is our duty to get maximum bang for their buck and invest in fully funded schemes that we know can be delivered."

He added:
"I will not continue with the former Mayor’s unrealistic and hollow promises.  The last administration's commitments amounted to billions of pounds worth of schemes that London could simply never afford."