Gatwick fires last-ditch warning over Heathrow expansion 'risks'

Gatwick Airport will fire a last-ditch warning about the "risks" of expanding rival Heathrow just hours before a committee chaired by Theresa May approves the first new runway in the south-east for decades.

Sky News understands that Gatwick executives will write to the Cabinet sub-committee on airport expansion on Monday in an eleventh-hour attempt to persuade ministers that it should be permitted to build a new runway.

A decision is expected to be announced by the Government on Tuesday following a meeting of the sub-committee, with Mrs May allowing Conservative MPs to publicly oppose the verdict.

Sources said that Gatwick's letter would reiterate the case for the Sussex airport to land a new runway ahead of Heathrow.

"We will focus on the benefits of competition, the relative cost of the two airports' plans, and the straightforward and clear path to delivery," an insider said on Saturday.

In addition to Mrs May, ministers on the Cabinet sub-committee include Philip Hammond, the Chancellor, and Chris Grayling, the Transport Secretary.

A decision next week will be followed by a year-long public consultation and then a final vote in the House of Commons.

People close to Gatwick said it would highlight the "difference in risk profile" of its scheme and that of Heathrow Airport, which is pushing for a more expensive project to construct a new third runway.

Another proposal, from Heathrow Hub, would extend and then divide one of the site's two existing runways.

"Heathrow's project carries considerable planning, financing and construction risks against Gatwick's very modest profile in respect of these risks," said a Gatwick insider.

"Gatwick has underwritten substantially all of the risks associated with its project through guaranteeing a cap on charges whereas Heathrow is asking the airlines and their passengers, and the Government to bear the risks of its project."

"That's what Monday's letter will highlight."

The owner of British Airways, International Airlines Group, has vehemently opposed Heathrow's plans, saying that it would unfairly bear much of the cost through higher charges.

IAG already pays close to £900m annually to Heathrow's parent company.

Executives at Gatwick have said the airport and its shareholders are prepared to commit to building a second runway under all circumstances because existing traffic growth there supports its expansion case.

Industry sources expect the Government to further growth in regional aviation capacity alongside the decision to grow at least one of the two largest London airports.

The Prime Minister's decision to suspend collective responsibility for the decision has been interpreted as a sign that she will give the green light to Heathrow, in line with the recommendation made last year by the Airports Commission.

A number of her top team, including Boris Johnson, the Foreign Secretary, bitterly oppose the expansion of Heathrow, while politicians such as Sadiq Khan, the Mayor of London, have publicly endorsed Gatwick's case.