(Photo: Daniel Schwen, via)It's less than 24 hours since Article 50 was finally triggered and we've already been dealt our first blow. According to Ryanair, the UK may not be able to fly to and from Europe for a period of time after Brexit.The budget airline has issued an alarming warning on the possible effects of Brexit on the travel industry, saying that aviation should be treated as a matter of urgency in our negotiations, as summer schedules for 2019 flights must be finalised by March of next year. Without striking a unanimous agreement with the EU, Britain will have to revert to WTO regulations that do not cover aviation, Ryanair said.Ryanair also added that it had already "pivoted growth away from the UK to other EU airports" and that it would not be basing any new aircraft in any of the 19 UK airports it flies to this year."It's become worrying that the UK government seems to have no plan B to maintain Britain's liberalised air links with Europe," Ryanair's chief marketing officer Kenny Jacobs said. "With Britain planning to leave the EU and its Open Skies agreement, there is a distinct possibility that there may be no flights between the UK and Europe for a period of time after March 2019."Open skies is an agreement between the EU and the US, which the UK will potentially be cut out of of it leaves Europe without a similar deal.