A passenger plane comes into land over a field containing horses at Heathrow Airport. Peter Macdiarmid/Getty Images Heathrow airport just scored a big win in its quest to build a third runway.

A government-commissioned report released today backed the west London airport's plans for expansion over Gatwick, which has also lobbied for a new runway over the past few years.

The Airport Commission "unanimously" backed expanding Heathrow over any other proposals, saying it could create £147 billion ($231 billion) worth of economic growth in the UK and 70,000 new jobs by 2050.

While the report says Gatwick's proposals are "plausible", the commission is firmly in the Heathrow camp — a big blow for Gatwick and a big win for Heathrow.

Sir Howard Davies, who chaired the inquiry, says: "Over the past 2 and a half years, the Airports Commission has reviewed the evidence without preconceptions, consulted widely, and followed an inclusive and integrated process.

"At the end of this extensive work programme our conclusions are clear and unanimous: the best answer is to expand Heathrow’s capacity through a new northwest runway."

Sir Davies says Heathrow is the best option for "business passengers, freight operators and the broader economy." In its report the Airport Commission also said that the "majority of airlines" preferred expanding Heathrow over Gatwick.

Heathrow CEO John Holland-Kaye said in response this morning: "This debate has never been about a runway, it's been about the future we want for Britain. Expanding Heathrow will keep Britain as one of the world's great trading nations, right at the heart of the global economy.

"The Commission has backed a positive and ambitious vision for Britain. We will now work with Government to deliver it."

London's airports are at capacity, and Heathrow and Gatwick have fought tooth and nail between each other to have their expansion plans approved. While Sir Howard's report is not binding to the government, it's a huge blow for Gatwick.

The government is not expected to respond to the report until later this year and the BBC reports that the Prime Minister's office is saying it won't make a "snap judgement."

But David Cameron faces pressure to do something about London's airports, whether it's approving a new Heathrow runway or not. The Airport Commission says in its report: "Further delay will be increasingly costly and will be seen, nationally and internationally, as a sign that the UK is unwilling or unable to take the steps needed to maintain its position as a well-connected open trading economy in the twenty first century."

Local residents at both airports have opposed expansion plans by the Airport Commission's report recommends several measures to lessen the impact of a new runway at Heathrow, such as banning night flights and an aviation noise fine.