MPs will decide later whether to expand Heathrow Airport and approve a third runway.
The vote, which will take place on Monday, is expected to show divisions between both Labour and the Conservatives.
The spotlight will today though be on Foreign Secretary Boris Johnson, who once threatened to lie down in front of the bulldozers if a third runway was approved at Heathrow. The foreign secretary will be abroad and will miss the vote, but it is currently unknown where Mr Johnson will be during the vote.
Labour is officially opposed to the expansion but Jeremy Corbyn has allowed MPs a free vote. It is thought around 40 Labour MPs could vote with the Government and against their party.
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