Efforts to persuade DC mandarins to leave Irish aviation alone has now moved into the sphere of international relations and strategic connectivity

Any retaliation would be a major blow to Aer Lingus in particular, whose business model in recent years has heavily focused on new North American routes

The Government has scrambled with extensive ongoing contacts with counterparts in Washington DC to defend Irish aviation against a threat of damaging retaliatory action over the Dublin Airport cap by the Americans.

Transport minister Darragh O’Brien has now revealed the extensive contacts that have been ongoing between himself and his officials and Trump administration transportation officials in recent weeks.