LONDON (REUTERS) - Prime Minister Theresa May is set to end decades of indecision by backing the expansion of Britain and Europe's busiest airport, Heathrow, finally kickstarting a project made more pressing by the vote to leave the European Union.
May and a small team of ministers will meet on Tuesday to choose between expanding Heathrow, to the west of London, or Gatwick, to the south - making a decision on airport expansion after more than 25 years of debate.
Key opponents of Heathrow expansion such as Foreign Secretary Boris Johnson, who as then London mayor said last year it would not solve capacity issues and the scheme was doomed to fail, will not be present.
Both airports are running at close to full capacity and big business argues that Britain needs a new runway to build trade ties and better compete with Paris, Frankfurt and Amsterdam.
While there are three options on the table - a new runway at Heathrow, lengthening one of its existing two runways, or a new runway at Gatwick - the government has indicated it will opt for a new Heathrow runway - the more ambitious and expensive option.
In 2015, a three-year independent inquiry set up by the government recommended that option, subject to a list of conditions over night flights, noise and air quality.
Last week May took the rare step of promising colleagues who oppose the decision that they would be allowed to publicly air their views, interpreted by the media as a strong signal it would be Heathrow as there are no high profile ministers who oppose its expansion.
The airports decision will be one of May's biggest moves since she became prime minister in July, and would contrast with the delaying tactics of her predecessor, who failed to act after having withdrawn a previous government's approval to expand Heathrow in 2010.
Transport Minister Chris Grayling will make a statement to parliament about the expansion at 1130 GMT (7.30pm Singapore time) on Tuesday. "There will be challenge and opposition whatever option we take," he told BBC television on Sunday, of the first full-length runway to be built in the London area for 70 years.
"We have to, in my view, take a decision that is in the interests of our nation, what delivers the best connectivity, the right approach for the future at a time when we want to grow international trade links, open up new opportunities."
The decision will be subject to public consultation before it is put to a vote in parliament in late 2017 or early 2018. Surveys show a majority of lawmakers back Heathrow expansion.
Five local councils around Heathrow including Maidenhead, the area May represents, have hired a law firm to fight Heathrow expansion. Other opposition groups have also said they are likely to consider legal action against a new runway there.
Costing either US$17 billion (S$23.7 billion) for the runway extension or US$22 billion for the additional third runway, Heathrow would be the more expensive project and face legal challenges over its environmental impact on densely populated west London.
But its established trade links with emerging markets strengthen its case in the wake of the Brexit vote. It also has the backing of the major airlines.
Gatwick, the country's no. 2 airport that mostly connects to Europe, argues it can build a runway more quickly and, at US$9 billion, more cheaply, and that its rural position means it would disturb fewer people.
Writing in the Telegraph newspaper, Howard Davies, head of the independent inquiry which backed Heathrow, said Brexit had made the case for Heathrow "overwhelming" given it handles more air freight and a greater number of long-haul inbound tourism.