Why the Scottish Nationalists are backing expansion for Heathrow

Parliamentary Business: How do you get Scottish salmon on to plates in Japan and China? You go through the London airport

The vast Tsukiji wholesale fish market in Tokyo, renowned for its tuna auctions, is filled with more than 400 wonders of the ocean, including live sea eels, pickled octopus, urchins and barracuda. China’s hunger for sea cucumbers has outgrown its commercial farms and the country has cast its nets as far as Sierra Leone for the sausage-shaped delicacies; meanwhile carp from West Lake in Hangzhou, near Shanghai, cooked in sweet and sour sauce, is one of the world’s finest fish dishes.

But for all this abundance of sea and fresh water-based fare, there’s one fish that these Asian powerhouses can only get by importing it from a source thousands of miles away – and that’s Scottish salmon. “Heathrow’s No 1 [exported product]… is Scottish salmon,” smiles Nigel Milton, who is the airport’s top lobbyist. “How do you get Scottish salmon on to plates in Japan and China? You go through Heathrow.”

Around £280m-worth of our pink-fleshed friends are flown out from west London every year, as well as crate upon crate of Scottish whisky. That’s the union in action – and it is certainly one part of a shared destiny the Scottish National Party is keen to foster. It is thought that Nicola Sturgeon, Scotland’s First Minister and the SNP’s leader, is hoping Heathrow will be allowed to build a third runway, at an estimated cost of £18.6bn – or at least that it will be able to expand one of its existing runways – once the Airports Commission produces its final report, which it is expected to do this month.

The SNP, it is understood, has been swayed by arguments that the additional slots opened up by expanding Heathrow would include new destinations north of the border, such as an Inverness route pledged by easyJet; the party has been spooked by Virgin Atlantic’s decision to end routes to Aberdeen and Edinburgh as the airport struggles to keep running at 99 per cent capacity. Heathrow’s chief executive, John Holland-Kaye, has claimed a west London victory would result in 16,000 Scottish jobs and £14bn for the country’s economy.

Sir Howard Davies, the former Financial Services Authority chairman who leads the inquiry, has had three years to decide what extra airport capacity is needed in the south-east, and where, as airports struggle to cope with passenger numbers.

It’s now a straight choice between Heathrow, which has just lost its crown as the world’s busiest airport to Dubai, and Gatwick, where a second runway would cost just over £9bn. Although the Government is not bound by the choice, it will almost certainly endorse Sir Howard’s recommendations. And there appears to be broad agreement that the inquiry, interminable though it has been, has at least been handled professionally.

Gatwick is probably the slight favourite: its environmental argument appears to be sounder and there are competition merits in turning it into a hub to challenge Heathrow. Politically, too, it would be easier for ministers should Sir Howard choose Gatwick for expansion. That’s because the Heathrow plan faces formidable opposition from Boris Johnson, Mayor of London, who has been asked to attend Cabinet meetings since returning to Parliament last month.

Yet Heathrow executives think that giving Mr Johnson a place at these meetings was a canny move. Yes, he could sound off about Heathrow if it wins, but his views would not carry ministerial weight; and given that his role is not a formal one, he would not be bound by collective responsibility – not that he would really have anything to resign from. And by the time Mr Johnson finishes his second and final term as Mayor next year, the Heathrow argument will have been settled, allowing him to become Secretary of State for a department with real clout as part of a reshuffle in late 2016 or 2017.

Heathrow wasn’t happy recently when I argued that Mr Johnson’s unofficial Cabinet role would do quite the opposite and put pressure on Sir Howard to make any choice as long as it’s Gatwick – or would at least signal to ministers that the airport is on course for recommendation.

I still think the potential for an embarrassing row with the party’s most popular figure – at a time when Tory divisions are already emerging over the EU referendum, civil liberties, and devolution – is a danger David Cameron would have foreseen. Which suggests that the Prime Minister is confident his Government will be approving Gatwick, rather than Heathrow, for expansion this summer.

If Heathrow does get the nod, however, Mr Cameron will be able to rely on the SNP’s 56 MPs to help him get the decision through the House of Commons. While a third runway probably wouldn’t need to be backed by an Act of Parliament, there seems to be an acceptance in the Heathrow camp that statutory approval would legitimise expansion in the face of what would be fierce opposition from environmental groups and local campaigners.

Given that the Tories have a wafer-thin majority of 12, and that many MPs would join Mr Johnson in voting against a Heathrow Bill, support from the SNP – a party that represents all but three seats in a country within the union – would allow the PM to claim he was acting in the interests of the entire UK.

Conservative ministers and the SNP could find themselves in the same division lobby and, for once, they could be very comfortable in each other’s company.

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