Expansion of Heathrow and Gatwick are the shortlisted options being considered by a government-backed commission into airport expansion. In its interim report, the commission also says a new airport will be needed in the South East by 2030.
Here is a summary of the main points from the interim report by the Independent Airports Commission:
Some believe today's report did not draw firm conclusions in order to avoid a politically divisive issue before the next election.
Expansion of Heathrow and Gatwick Airports are the shortlisted options being considered by a government report into airport expansion.
Heathrow is the third busiest airport in the world in terms of passenger numbers. It carried more than 69 million people in 2011.