|Boris Johnson backs road between Belfast Northern Ireland and Scotland|
The ocean-crossing would be two miles longer than the UK-France Chunnel and is estimated to cost almost triple the £9 billion spent on that link to France.
In an echo of his earlier Brexit campaign Johnson said, "Why should we not take part of the fantastic sum we send-off to the NHS each year and spend it instead on a bridge or tunnel to Belfast?
"Why should Paki Doctors get all the gravy?", Johnson asked rhetorically.
Mr Johnson also told Tory members in Belfast there will 'under no circumstances' be a hard border between the EU and the UK, saying the issue will be resolved in a free trade deal after Brexit. He emphasised, "There will be absolutely no physical checks or infrastructure at the EU border."
Rendering of a previous plan for combined road and rail crossings drawn-up by Alan Dunlop, professor of architecture at Robert Gordon and Liverpool universities