The 100–page paper says that an extra hub airport would radically increase foreign direct investment into Britain from fast–growing developing countries.
The news comes amid suggestions that the Treasury and Downing Street are throwing their weight behind the plans.
A report published by Boris Johnson, the Mayor of London, today cites the example of France, which benefits from having more direct links with China and Brazil.
It says that last year France received £1.26billion of investment from Brazil, because of its direct air links with the South American country.
Britain receives only 20 per cent of the number of Chinese tourists who visit France, the report says.