Sir Roy McNulty, Gatwick’s chairman, has written to prime minister David Cameron setting out eight pledges including a guarantee that the runway will be operational by 2025, subject to the government making a decision by October and the “normal planning timetable”.

Gatwick is also promising caps on passenger fares and the number of people “most affected” by noise from the expansion.

McNulty added that building a second runway would not require any public funding and it would not breach the government’s air quality limits.

The government has promised to make a decision this summer on whether Heathrow or Gatwick should be allowed to build a new runway. The Airports Commission last year recommended a third runway at Heathrow.

“We have submitted a considerable amount of new and updated material to the Department for Transport over the last five months,” said McNulty in his letter.

“We have set out in more detail how Gatwick would create a second world class airport for the UK and meet the future aviation needs of the country.

“The expiry of a 40-year moratorium on a new runway at Gatwick means Britain can finally solve this policy problem and secure the economic growth it needs at a fraction of the environmental cost of the alternatives.”

Gatwick signed a deal with West Sussex County Council in 1979 guaranteeing that it would not build a second runway before 2019.