The airline owned by Sir Richard Branson has backed plans to build a new runway at Heathrow.
Sir Richard said the government should make a clear commitment
Virgin Atlantic Airways made its comments in the final week of consultation on airport expansion in the South East.
The company also supports further runway development at Gatwick - but is not in favour of a new airport at Cliffe, in north Kent.
Virgin, which currently operates 113 flights a week from Heathrow, said a new runway there was the most "economically viable" option available at an "acceptable" cost to the environment.
The UK and Heathrow in particular is in serious risk of losing its pre-eminence in European and world aviation
The company wants in the short term to see Heathrow's two existing runways change to "mixed-mode" use - so flights could constantly take off and land on both strips.
Virgin also called for the "earliest possible" development of a second runway at Gatwick, where it runs 45 flights a week.
A spokesman said: "The construction of Cliffe and possibly of a mega-Stansted would do more harm to the environment than the development of Heathrow, Gatwick
and more restrained development of Stansted."
He said any further runway capacity, were it necessary, should only then be considered at either Stansted or Gatwick.
Plans for an extra runway at Heathrow have stirred anger
Sir Richard called for special government legislation to smooth the passage of a new short runway at Heathrow.
He said: "The UK and Heathrow in particular is in serious risk of losing its pre-eminence in European and world aviation.
"Business, tourism, trade unions, air users and the aviation industry all demand a clear commitment from government to the development of new runway capacity and a detailed timetable for its delivery."
The government's decision will be published in an aviation White Paper at the end of the year.