Theresa May is to allow a short pause on whether to give the go-ahead to a new runway at Heathrow so that Cabinet ministers can express their views.
Sources in Whitehall told the BBC that expansion at Heathrow is the clear front runner.
However, the prime minister has made it clear she wants to hear the wide-ranging opinions of colleagues.
The BBC has been told the Cabinet will discuss the issue tomorrow but no final decision is expected.
It will then be left to the Economic Affairs (Transport) sub-committee, chaired by Mrs May, to make the final choice on whether to back Heathrow or Gatwick.
One option being looked at is for that committee to meet next Tuesday, 25 October, with an announcement on the same day.
Government officials believe that a third runway at Heathrow or an expansion of the existing runways are now the leading options, although it has been made very clear to me that no final decision has been taken.
In the Cabinet there are splits.
Boris Johnson, the foreign secretary, has been a long-time opponent of Heathrow, describing it as a "fantasy".
Justine Greening, the education secretary, is also opposed.
Heavyweights who have previously been pro-Heathrow include Liam Fox, the international trade secretary, and Sajid Javid, the communities secretary.
Philip Hammond, the chancellor, has been careful not to express a view, but senior Treasury officials have made it clear they believe Heathrow is the better option for boosting economic growth.
That is because it is closer to many more population centres in the UK compared to Gatwick, including Bristol and the South West, the Midlands and the north of England.
One other Cabinet minister told me: "I would do both Heathrow and Gatwick - that would tell the world Britain is open for business."
That option is not officially on the table, although if the government does back Heathrow, it could make positive noises about Gatwick expansion in the future.
It has been pointed out to me by Whitehall sources that expansion at Heathrow more easily fits with the government's overall transport strategy.
High Speed 2, the fast rail link planned to run between London and Birmingham, Leeds and Manchester, will run close to Heathrow.
The Scottish government also backs Heathrow, as does the business lobby group the CBI.
Labour is also expected to officially support Heathrow expansion, despite opposition from the shadow chancellor, John McDonnell.
Heathrow's greatest challenge is on the environment and noise, and many within the government believe a myriad of legal challenges are inevitable from local groups and environmental organisations if a third runway is given the go-ahead.
The Daily Telegraph reported on Monday that the prime minister has been warned by some ministers that there will be "chaos" if she backs Heathrow because of the legal challenges, which could last "for decades".