Details of plans for a third runway at Heathrow Airport are expected to be set out later today.
Transport Secretary Chris Grayling will clarify plans for the west London hub at a meeting of the Cabinet’s economic sub-committee on Tuesday morning, Sky News understands.
The details will then be discussed by Theresa May’s full Cabinet, which meets at 9.30am.
If the plan receives the Cabinet’s backing, the transport secretary will likely update the House of Commons.
MPs will then vote on the plan no later than 21 sitting days after its publication.
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Image: Zac Goldsmith and Boris Johnson are both against the expansion
Key Tory Heathrow opponent Boris Johnson, the foreign secretary, is notably not on the sub-committee.
A third runway at Heathrow was given the green light in 2016, but remains a controversial matter for nearby residents, politicians from all parties, environmentalists and business leaders.
Yesterday, The Daily Telegraph reported that Mrs May is considering not handing her MPs a free vote on Heathrow over fears that dozens of anti-Heathrow Tories could scupper a key pledge.
Ministers are concerned that granting MPs a free vote will set a “dangerous precedent” which will force the government to hold free votes on future infrastructure projects.
On being elected MP for nearby Uxbridge in 2015, Mr Johnson said he would lie down “in front of the bulldozers” to halt the expansion.
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Image: Trade minister Greg Hands is also opposed
Chelsea and Fulham MP Greg Hands is also a top Tory campaigning against a third runway.
If he and Mr Johnson went against a three-line whip they would be forced to resign, with suggestions they could be out of the country on official business when the vote takes place.
Other prominent Conservatives opposed to the third runway include Zac Goldsmith, who resigned as Richmond Park’s MP over the issue before winning his seat back from the Lib Dems last year.
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There is also concern that Labour will oppose the third runway after its manifesto said certain environmental conditions would have to be met to support the expansion.
If Tory MPs are given a free vote, it is understood more than 30 are prepared to rebel, resulting in a likely defeat for the government.