By Michael Allen
Multi-billion-pound investment plans for Heathrow will be announced by the airport's bosses later this week.
They are also expected to announce a rise in charges for airlines that use the airport, which could result in higher ticket prices.
Transport Secretary Patrick McLoughlin and London Mayor Boris Johnson will give evidence on future aviation strategy to the House of Commons Transport Committee on Tuesday, hours before the Heathrow investment plans are published.
The investment plans are expected to reveal proposals for £3 billion of spending between 2014 and 2019.
Currently airlines have to pay airport fees equivalent to about £19 per passenger but by 2014 this could be as much as £25.
Heathrow bosses are currently awaiting a decision on whether Heathrow will retain its position as the UK's main hub airport.
The airport management, led by chief executive Colin Matthews, would like the future of the airport, and whether or not it will receive a third runway, to be decided sooner rather than later.
But, the final report by the Government-appointed commission looking into aviation strategy, led by former Financial Services Authority chief Sir Howard Davies, is not due to be published until summer 2015.
Mr Johnson and others have been critical of what they see as the slow timetable for the Davies Commission.
Unlike the coalition Government, the London mayor is not in favour of a third runway at Heathrow and would prefer to see a new airport to serve London in the Thames Estuary.
When Mr Johnson and Mr McLoughlin appear in front of the Commons Transport Committee on Tuesday, the Transport Secretary is likely to tell MPs that decisions on airport expansion can not be rushed if they want to find the correct solution.
However, critics have accused the Government of kicking aviation decisions "into the long grass".