Mayor of London Boris Johnson today set out new plans for the financing of the controversial Crossrail scheme, which will see a new rail link established between Maidenhead and Heathrow in the west, to Shenfield and Abbey Wood in the east via twin tunnels under central London.

Below, speaking exclusively to us, Deputy Mayor of London and Chief of Staff Sir Simon Milton explains the plans and what they mean for you...

"Today, Boris Johnson has announced a major step forward in delivering the Crossrail project by setting out how the main financial element of the business contribution is going to be raised.

Crossrail is London's most important project for a generation. When complete it will increase London's overall rail capacity by 10% and will relieve horrendous congestion on the tube, DLR and overground rail which will otherwise only get worse as our population grows. All three major parties are committed to the project.

The real economic benefits will be felt all over London - from regenerating otherwise run-down areas to boosting the spending power in leafy suburbs whose citizens will find it easier to access jobs in the main central economic areas of the capital.

Crossrail is also an expensive project and is budgeted to cost £15.9billion.

Whilst the payback over time will be many times this number the cash needs to be found now to dig the tunnels, lay the track, build the signalling and buy the trains.

But the country is emerging from the longest recession it has ever experienced but we know that full economic recovery is going to take years and that there will be setbacks along the way.

Boris's main concern has been to ensure that the bulk of the funding will come from those areas that will benefit most from the new line and that small and medium sized businesses - the backbone of London's economy - are not asked to bear a disproportionate burden.

The most important lesson we can learn from previous recessions is that we must not cut back on infrastructure investment if we want our economy to resume a growth trend and keep us competitive.

Roughly a quarter of the costs will met from levying a 2p supplementary business rate on all businesses with a rateable value of over £55,000. This is a higher rateable value threshold than was originally proposed following comments received from businesses to our initial proposals which set the threshold at £50,000.

The change will remove some 4000 businesses or 8% of the total from paying the new tax and will particularly help small and medium sized businesses particularly in outer London. 70% of the tax will be now raised in boroughs with Crossrail stations and half will come from the main business districts of the West End, the City and Canary Wharf. As a result of the £55,000 threshold only one in six business properties in London will be liable to pay the supplement - so the vast majority of London's business community will not have to pay anything.

Nobody relishes paying additional tax but we think that this is the fairest way to spread the load and will help deliver what we all want to see - a fantastic new public transport service for London that will help deliver jobs and growth in the future."

Sir Simon Milton, Deputy Mayor and Chief of Staff