Better to America: that is the aim of the Edinburgh airport chief executive Gordon Dewar. Allowing transatlantic airline passengers to clear US arrival formalities while still in the UK “would be incredibly powerful” for the Scottish hub, he said.

Mr Dewar is seeking agreement for the Scottish capital to be the first airport in the UK offering “preclearance” of the American border process.

The system, already in place at airports in Ireland, Canada and elsewhere, involves US Customs and Border Protection officers assessing passengers before they board flights to America. Assuming the traveller passes the checks, they are effectively on US territory.

On touchdown at the destination airport, passengers are treated as domestic arrivals – swerving queues for immigration that can take two hours or more.

Travellers with a connecting flight need not collect their luggage, as bags are checked through to the final destination. Anyone who is refused admission does not need to be flown back to their starting point.

“It's a phenomenal service,” Mr Dewar told The Independent. “Anybody who's used the Dublin service knows the advantages. Not only do you have certainty of timing because you arrive as a domestic passenger, but your connection times are better because they know you'll get through.

“You don't have to recover your baggage and put it through customs in the American airport before reloading it. There are so many advantages.

“This is hugely popular with customers, and I suspect Dublin has twice as many American routes as it would have without preclearance. That’s exactly why we think it would be incredibly powerful for Edinburgh, and we are pursuing it.”

The system requires governmental approval – which the Edinburgh airport boss believes could be made easier because of President Trump’s “enthusiasm for Scotland.”

Scotland’s first minister, John Swinney, raised the subject when meeting Mr Trump on visit to Aberdeenshire in July.