London Mayor Boris Johnson has said that a new airport in the Thames Estuary - so-called Boris Island - would cost far less than is claimed in today's Airports Commission report.
According to the report, the scheme could cost between £82 billion and £112 billion and would result in airport charges around three times higher than those projected for Heathrow.
Johnson insisted the total cost would be around £50 billion - £20 billion for transport links and £30 billion for the facility itself, which he predicted could be funded from private investment.
Here is a summary of the main points from the interim report by the Independent Airports Commission:
- Heathrow is effectively full and Gatwick is operating at more than 85% of capacity
- Aviation demand "likely to increase significantly between now and 2050"
- Demand is likely to be concentrated in the South East, where more people live and wages are higher on average
- There is a need for one additional runway to be in operation in South East by 2030 and likely to be demand for a second one by 2050
- Proposals for additional runways at Heathrow and Gatwick were short-listed. 'Boris Island' proposal in Thames Estuary will be looked at in first half of 2014 and may join short list.
Conservative MP Zac Goldsmith said he would not stand as a Conservative party candidate if David Cameron regaled on his "No ifs, no buts" earlier position on building another runway. Speaking to ITV News he said:
"If we go into the next election with a green light for Heathrow expansion, I would not able to stand as a Conservative."
Of the three options for expansion presented by Heathrow Airport Ltd in the summer, the Airports Commission is only progressing one of them: the plans for a new runway to the north west of the existing airport.
The other Heathrow idea being investigated by the Commission comes from a pressure group called Heathrow Hub: the extension of one of the current runways.
The proposal is to build a third runway to the north west of the existing airport. It is a different proposal to the one approved by Gordon Brown when he was Prime Minister.
The new runway is further to the west - and anyone who knows this area will work out it brings the runway of Britain's busiest airport into conflict with Britain's busiest motorway, the M25. Look at the plan and you will see the runway is built over the top of the motorway.
That is not unusual. At Paris' Charles de Gaulle airport, a motorway passes under one of the runways in a tunnel. But it does mean this option is not cheap.
Proposals for an expansion of Birmingham Airport have not been shortlisted as part of a report published this morning.
The Airports Commission report has looked at ways to maximise airport capacity.
However, it did say that Birmingham Airport could be considered as a potential option for a second new runway by 2050.
The Commission report's findings mean the village of Sipson near Heathrow Airport could later be affected if the original plans to extend the runway is supported.
Heathrow's bosses say their runway plan on a site to the north west of the airport - now on the Davies' shortlist - will mean less noise.
Local groups say the north west plan will require significant demolition in the villages of Longford and Harmondsworth and anti-Heathrow expansion group Hacan vowed today to fight the Heathrow plans.
However airlines, as well as the CBI and the London Chamber of Commerce, welcomed the commission's report.
Thirty thousand people would be negatively affected by plans to build a new runway at Gatwick Airport, the Gatwick Area Conservation Campaign said.
The campaign group have drawn up a list of possible flight plans, should the project be given the go ahead.
The plans were made in consultation with air traffic control experts, as airports are currently not required to publish flight paths before the runways are built, Brendon Sewill, Chairman of the campaign said.
The plans were made in consultation with air traffic control experts, as airports are currently not required to publish flight paths before the runways are built, Mr Sewill said.
Mr Sewill said a new runway would mean an extra thirty thousand people would be afflicted with noise pollution, bringing the total across the area to 42,000. He said:
"We are not surprised as we always expected matter into focus, but we know we are in for a big battle.
"Howard Davies says we don't need a new runway until 2030 and the plans are not until 2040, but we need to fight like mad to stop a decision that will afflict the whole of Sussex, and much of Surrey and Kent.
"We are agree with national environmental organisations that any new runway anywhere is not compatible with the national enviromental policies.
"Also, the main concern about a new runway in Gatwick is that it would mean the inwards migration of a large number of people from the rest of UK, or from the EU with the need for 40,000 new houses, according to West Sussex County council."