David Cameron, George Osborne and key Cabinet ministers will meet tonight to discuss how to respond to recommendations that a third runway should be built at Heathrow.
Downing Street said a decision on how to proceed on airport expansion will be made, which will go before the Cabinet.
Mr Cameron has previously said a decision would be made by the end of the year but the promise later appeared to be watered down. No 10 repeated its commitment to providing a "clear direction" by the end of the year.
The Davies Commission recommended the construction of the controversial third runway in a report in July.
Transport Secretary Patrick McLoughlin, Environment Secretary Liz Truss, Scotland Secretary David Mundell, Communities Secretary Greg Clark, Cabinet Office Minister Oliver Letwin and Chief whip Mark Harper will also attend the Cabinet sub-committee on airports to consider its recommendations.
Business Secretary Sajid Javid will miss the meeting because he is on a visit to India and the Energy Secretary Amber Rudd is also expected to be unable to attend.
London mayor Boris Johnson has not been invited to the meeting and no MPs from the capital will be represented.
A Downing Street spokesman said: "The sub-committee will come out with a conclusion which will go to Cabinet."
There is speculation that the Government is set to announce a delay in making a final decision.
Heathrow anti-noise campaigner John Stewart, who chairs the residents' group Hacan, said that would demonstrate "just how difficult it will be to build a third runway".
He commented: "The last Labour government tried and failed. And now this Government has run into real obstacles.
"Heathrow would require almost 1,000 homes to be demolished and part of the M25 to be moved and put in a tunnel.
"It would mean a quarter of a million more planes flying over the city with the biggest aircraft noise problem in Europe and could cause air pollution to exceed the EU legal limits.
"Many of these problems won't go away however long the final decision is delayed. The Government should face up to the reality that a third runway is unlikely ever to see the light of day."
Chambers of Commerce from across the country wrote to Mr Cameron on Wednesday demanding that he approve Heathrow expansion by the end of year.
They warned that any delay raised "grave concerns" about the future credibility of the new National Infrastructure Commission and cast doubt about whether it would have real power to make big decisions.
The letter stated: "Heathrow expansion will increase our area's connectivity, add more long-haul connections, and help us to boost exports, investment and tourism.
"Given how long it has taken to get to this stage, and to the Airports Commission's final recommendations, we are deeply concerned at the prospect of any further delays.
"Our businesses tell us that ministers' statements on growth and exports mean little if the Government cannot take the tough decisions needed on key infrastructure projects.
"Our businesses want delivery, not more reports and recommendations. We want to see Heathrow expansion approved by the end of the year, as promised."
The letter was signed by more than 20 Chambers of Commerce from across the country, including Glasgow, Liverpool, Cornwall, the North East, Northern Ireland and Leeds.