In a rare move, ministers opposed to the decision will be allowed to voice their views when the preferred option is revealed, a spokeswoman for Prime Minister Theresa May's Downing Street office said.
The unusual arrangement comes amid mounting speculation that the government will back a new runway at Britain's busiest airport, Heathrow, after years of debate and wrangling over the issue.
The decision on whether to approve this option or instead expand London's Gatwick airport will be taken by a cabinet sub-committee on transport, which includes May and Finance Minister Philip Hammond.
The spokeswoman said the decision had been "delayed for too long" and should be made now "in the national interest", after cabinet ministers met Tuesday to discuss the matter.
The reinforcement of London's airport infrastructure has been the subject of debate for many years, even though the city already has five airports.
Business communities have long been lobbying the government to expand one of the capital's existing airports, which they say cannot keep up with rising air travel demand.
In July 2015, a government-appointed commission recommended building a third runway at Heathrow, in the west of the capital, to ease congestion.
The report added that a rival bid for a second runway at Gatwick airport south of London, which is backed by London Mayor Sadiq Khan, was also "plausible."
A decision was delayed, however, pending further investigation into the environmental impact, including noise and pollution.
Environmental groups fiercely oppose any airport expansion in the British capital, parts of which already routinely breach EU air pollution limits.
Heathrow expansion also faces opposition from lawmakers in residential west London, where hundreds of homes would have to be demolished to accommodate a third runway.
But business groups say it would boost trade and help Britain keep up with rapidly expanding airports in the Middle East and Asia.
They also want to send a strong message on London's economic future amid uncertainties surrounding Brexit.