Two new runways could be built at Gatwick, increasing passenger levels at London's second airport from 32 million to around 115 million.
The plan, the most radical of three options in the government's consultation paper on air transport, would lead to the loss of 430 homes, a number of historic buildings, a conservation area, and hundreds of acres of agricultural and rural land.
The two other options envisage the building of a single extra runway close to the existing one or further south, taking annual passenger levels beyond 60 million and 80 million respectively.
The consultation paper said that, with no new runway or terminal at Gatwick, the capacity might increase to 46.5 million passengers a year through greater use of larger planes and off-peak flights.
Gatwick, located 20 miles south of the capital, is already the busiest single-runway airport in the world. It had not featured in the government's first set of plans, published last July, as officials had agreed that there should be no expansion at the airport before 2019.
The July plans suggested extending London's Heathrow and Stansted airports, and possibly building a new facility in Kent.
However, after a challenge from Kent and Essex councils, the high court ruled last year that Gatwick should be included in the consultation process.
Announcing the plan, the transport secretary, Alistair Darling, said that air transport was "critical to the future success of the economy".
Despite the slump in air travel since the September 11 terrorist attacks on the US, the government believes that the long-term outlook is for growth.
In the past 20 years, the Department of Transport says, the number of passengers using British airports has trebled, and the number of flights has doubled.
However, residents have vowed to fight the Gatwick plan. Brendon Sewill, the chairman of the Gatwick area conservation campaign, said: "Any new runway ... would be an environmental disaster for Surrey, Sussex and the west of Kent."
Mr Sewill predicted that an extension would mean "double the number of aircraft, double the noise, double the number of flight paths, double the pollution and double the road traffic".
Brenda Dean, a Labour party peer and the chairman of lobby group Freedom to Fly, said that it was important to finalise extension plans.
"We cannot allow London's position as the world's leading financial capital, and the job prospects of thousands of workers, to be put in jeopardy by further legal wrangling," she added.
A final decision on which airports are expanded is expected in a government white paper later this year.
