A cable car connecting the Royal Docks with North Greenwich is set to be built, after it was given the green light by City Hall.

Planners in Newham and Greenwich had already given their approval to the link, which will carry 2,500 passengers an hour 50 metres above the Thames.

Deputy Mayor of London Sir Simon Milton signed off on the plans last night on behalf of Boris Johnson.

Mayor Johnson said: “With permissions signed and sealed we are now a significant step closer to being able to cruise the east London skyline via an elegant cable car spanning the mighty Thames.

“It will be a truly exhilarating way for Londoners and visitors to explore our great city whilst providing a much needed river crossing to support the once-in-a-lifetime regeneration of this easterly quarter of the capital.”

The mayoral sign-off marks the end of a long and drawn out planning process for the Thames cable car.

Discussions on funding - expected to come from a third parties, sponsorship and fare revenue - are ongoing.

A contractor is due to be appointed later this year.

It is still unclear whether the link will be up and running in time for the London 2012 Olympics.

The project was put on hold after campaigners pointed out that it would pass through the public safety zone at nearby London City Airport.

Councillors in Newham and Greenwich were told to withdraw their planning grants after City Hall ordered a review of the plans.

A subsequent report by the National Air Traffic Service found the risk of an aircraft accident affecting the cable car would be less than one incident every 15 million years.