The timetable of deadlines has been drawn up by the International Olympic Committee (IOC) and outlines key milestones which need to be reached each year to ensure the Games are delivered on time.
According to the new programme, plans for all the facilities and sporting venues must be finalised by 2007 so that 'above-ground construction' can start in 2008.
Speaking on Friday after an `orientation seminar' with 2012 organisers in
London, IOC Olympic Games executive director Gilbert Felli told a news conference: `The master schedule we have provided is a big step forward for the organising committee and the IOC.
'It is a guideline of what we have to do over the next seven years. We started this with Sydney in order to understand what has to be done every month up to the Games.'
London 2012 vice-chairman Keith Mills added: 'Things are happening right now. We are drilling very large holes in preparation for establishing the power lines, sewage systems and other utilities.
'[However] we will see the major building works coming out of the ground in 2008 - that's when things will start happening on the surface.'
In the meantime, the IOC has begun negotiating a sponsorship plan to help fund the Games and it is expected the main sponsors will be unveiled by the end of next year.