LONDON, UK - With Europe still struggling to build sustained growth, many governments are looking to emerging economies in Asia, Africa and South America to boost trade.  A rivalry is emerging among the continent's main airports to provide the fastest links to these hubs. London's Heathrow airport, one of the world's busiest, fears it is being left behind.

Four years ago, environmental protestors from Greenpeace demonstrated atop a passenger jet at London's Heathrow airport.   The stunt gained widespread media attention, and the battle for the future of Britain's aviation industry is still being fought.

Joss Garman is a senior campaigner with Greenpeace.

"Britain is already very well served by airport capacity and the problem is that a huge amount of that capacity is being taken up by short-haul flights to destinations less than 500 kilometers away," said Garman.  "So places like Paris and Manchester [are] easily reachable by train, which is ten times less polluting."

The British government has ruled out building a third runway at Heathrow and has no current plans to expand other airports.  But business groups say Britain is being held back.

Nicola Walker is head of infrastructure at the employers' organization, Confederation of British Industry.  Its offices overlook the Crossrail construction project, one of the capital's biggest infrastructure investments.  Walker says Britain needs to be more ambitious.

"Our current international hub Heathrow is running at 99.2 percent capacity, and we don't believe that there's the opportunity to put on new links to those high-growth emerging markets that businesses really want to attack," Walker noted.

That means markets like Chongqing in China.  Chongqing has grown from a small regional city to a manufacturing hub, home to an estimated 7-million people.

Additionally, Sao Paolo, Brazil is seeing a huge influx of European businesses keen on trying to exploit old colonial ties.

Research by the British Chamber of Commerce claims two-thirds of business leaders in Brazil, China, India, South Korea and Mexico are more likely to trade with France, Germany or the Netherlands rather than Britain, because they offer more direct flights.

Independent aviation consultant Peter Forbes says London's lack of direct flights means it is losing out to rivals.

"Frankfurt for example has, I think, something like seven routes into China in comparison with Heathrow's four," said Forbes.  "But Germany has a lot more trade with China and from their point of view it's good to have those links."

London Mayor Boris Johnson wants a new airport built in the Thames estuary. The architecture firm Foster and Partners, which designed Beijing's airport, has submitted plans.  But with Britain back in recession, analysts say it will be difficult to justify the estimated price tag of $80 billion. The government says it will make a decision later this year.