A cycle hire scheme that more than 9,000 people have already signed up for will be officially launched by London Mayor Boris Johnson later.

The Cycle Hire Project will enable people to use bicycles stored at docking points in central London.

To begin with, the scheme will be available to those who sign up for membership.

They will then receive a key which costs £3, with membership costs at £1 for a 24-hour membership, £5 for seven days and £45 for an annual membership.

The first 30 minutes of any journey will be free, and the next 30 minutes will cost £1, with rising costs for journeys of more than one hour.

Casual users will be able to hire cycles around four weeks after the launch.

The cycles, which will be regularly maintained, will not have locks and they will be the responsibility of the hirer while in their possession.