Transport secretary Alistair Darling will announce within the next two weeks how Britain can tackle an anticipated doubling in the number of air passengers over the next 30 years. Options to be considered include new runways at Heathrow, Gatwick and Stansted airports and a new Thames-side airport.
Mr Darling will also deal with regional airport expansion - including contentious issues such as whether to build up Glasgow or Edinburgh airports as international hubs and whether to build a new airport at Birmingham.
A consultation paper will be issued. Decisions on which options to go for will be made by the autumn, when a white paper will be published. It is understood that the possibilities have already been narrowed to four combinations:
* The Cliffe airport and one new runway at Stansted;
* New runways at Heathrow and Stansted, plus a new runway at Gatwick after an agreement not to build one expires in 2019;
* One new runway at Heathrow and two new runways at Stansted.
The report is understood to have ruled out plans for expansion of Manstone airport in Kent to take international flights, largely because it would need an upgraded rail link. Instead, Manston could become a freight centre expanding to the size of Luton airport. Southampton and Luton airports may be expanded to take more continental and charter flights.