The long-awaited decision on airport expansion is expected to be made around midday today.
Transport secretary Chris Grayling will make a statement to Parliament, with Heathrow favourite to get the green light over Gatwick.
However, a final decision won’t be made until a year-long consultation process is complete.
Last year, the Airports Commission led by Howard Davies recommended a third runway at Heathrow over extending one of its other runways and a new one at Gatwick.
Writing in the Telegraph yesterday Davies said overseas the lack of a decision is seen as a “symbol of Britain’s inability to decide on its future as a trading nation”.
“The need for a clear strategic direction is more important since the referendum result,” said Davies. “The rhetoric about becoming a European Singapore with a ‘blue water’ trading focus seems empty if we cannot connect to the new markets we wish to serve.”
Political heavyweights including Boris Johnson and education secretary Justine Greening are among a number of MPs ready to oppose expansion.
Johnson will say will say that while he is a supporter of a "global Britain" after Brexit, an additional runway at Heathrow will increase pollution and noise levels.
Following the announcement Prime Minister Theresa May will give MPs "exceptional and limited" freedom to criticise the government's final decision - although they will not be allowed to campaign against it.
Construction is not likely to begin until 2021, the Airports Commission has said.
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