Liberal Democrats have underlined their opposition to any airport creation or expansion in the South East after Conservative calls for increased capacity.
The party is to rule out support for the so-called "Boris island" proposal being pushed forward by Mayor of London Boris Johnson that would create an airport in the Thames Estuary.
It is also set to reaffirm its opposition to any new runways at Heathrow, Gatwick or Stansted. Although that mirrors the commitment made in the coalition agreement, Tory MPs from the Free Enterprise Group have been pushing for each of the airports to be expanded over the next decade.
Last month Transport Secretary Justine Greening delayed a consultation on future UK airport capacity amid suggestions of divisions within the coalition on the direction to take.
The proposals, which will go before party members at the Lib Dem autumn conference next month, call instead for an independent study to find a location for a new hub airport or an existing one that is suitable for expansion.
Julian Huppert, co-chair of the party's transport committee, said: "Liberal Democrats have always opposed a new runway at Heathrow because it is in an appallingly bad location, with a quarter of all those in Europe affected by aircraft noise living under the Heathrow flight path.
"In the same vein, mixed-mode and night flights would cause unacceptable noise levels and air pollution for thousands of Londoners. You can't have one of the world's noisiest and busiest airports in the heart of West London's suburbs.
"With Birmingham looking to expand, Stansted only half full and Gatwick expanding into emerging markets, regional airports and other airports within London can meet demand for the short to medium term. Especially if we provide them with the transport links they so desperately need.
"We recognise, however, that a single, hub airport - rather than a constrained Heathrow with multiple satellite airports - would be better for the environment and better for the economy in the long term. Even three runways at Heathrow would only be a medium term solution."