Parts of the 2012 Road Cycling course are to be trialled in this year's Tour of Britain.
The final stage of the prestigious event will take in Regent's Park and elsewhere on the planned Olympic route.
Hundreds of thousands of fans are expected to line the course, which will also include a range of London landmarks including Tower Bridge, St Paul's Cathedral and Westminster.
The six-stage race taking in stages throughout the UK will culminate in 20 laps of a course around St James' Park.
Sports Minister Richard Caborn said: "By hosting fantastic events like the Tour of Britain we are showcasing the UK's talent in holding world-class sporting occasions.
"This is especially important as we prepare to welcome the Tour de France in 2007 and the London 2012 Olympics.
"The Tour of Britain gives people across the country the opportunity to watch world-class elite athletes performing at their very best.
"I hope this will inspire more and more people to take up cycling and help carry on Britain's proud tradition of producing outstanding cycling champions."
The 2006 Tour will start in Glasgow on 29 August, with stages following from Blackpool to Liverpool, Yorkshire (route TBC), West Midlands (route TBC), Rochester to Canterbury the finish for the first stage of the 2007 Tour de France.
The London stage from Greenwich to St James' Park via Tower Bridge, St Paul's and Regent's Park will be the largest cycling race ever staged in London.
Olympic champion Bradley Wiggins, who is hoping to ride this year's event as part of said: "It looks like it will be a fantastic route.
"It's going to go past where I used to live in Maida Vale and I used to dream of riding in big races. Now there's one right on my old doorstep."
15 May 2006