Thomas Heatherwick, who created the cauldron in which the Olympic flame burned for the duration of the London Games, helped design the new bus, commissioned by London Mayor Boris Johnson.

BBC: Prince Harry and David Cameron in New York to promote UK

Wrightbus was originally awarded the contract in January 2010 to design a new bus for London.

BBC: Northern Ireland

The new Routemaster bus for London has had its launch delayed for a week due to a paperwork delay.

BBC: Week-long wait for London's new Routemaster bus

Mr Johnson, who has long campaigned for a new bus for London, visited Wrightbus last November and described the design as a piece of "world class technology".

BBC: Northern Ireland

It was the first time in 50 years that a new bus has been designed for London commuters.

BBC: Northern Ireland