Britain faces "economic stagnation" unless another major airport is built in south-east England, London Mayor Boris Johnson has said.
The Government has ruled out more runways at London's airports but Mr Johnson, and others, have argued for a new hub airport in the Thames Estuary.
Launching a report on airport capacity, Mr Johnson said a new hub airport in south-east England had to become a pillar of the Government's planning for economic growth.
Developing such an airport outside south-east England was unworkable, with the possibility of foreign airlines abandoning London and instead going to European rival airports.
Mr Johnson said: "London's historic aviation links have provided the capital and the nation with great riches. However, the global economic geography is shifting and distant cities are rocketing up the league tables of global trade. The old order is passing. Our airports are unable to serve the young bucks that are set to drive the world forward.
"In the next 15 years 75 million Chinese households will enter the middle classes. It is a phenomenal market and we need our engineers to be able to hop on a plane and build their infrastructure. We need their business leaders to fly in and consult with our contract lawyers. However, their business is already being snaffled up by our friends on the continent who chortle at our continued inertia.
"There is no doubt that to do nothing will lead to economic stagnation. The Government must now grasp the nettle and begin serious plans for the multi-runway solution that can keep London and our great nation in the premier league of the global economy."
Simon Walker, director general of the Institute of Directors, said: "We welcome the mayor's valuable contribution to the debate on the future of aviation. London used to be at the cutting edge of transport development, but its status as a global hub city is under threat.
"More airport capacity is needed now more than ever."