If the UK leaves the EU without a deal in March, more than one-third of all Irish air traffic could be grounded.

According to the European Commission and the Irish Aviation Authority (IAA) if the UK exits without a deal, EU rules on air transport will no longer apply, effectively grounding all flights between the UK and the EU, the Irish Times reports.

An IAA spokesman said: “There would need to be a new agreement in place to maintain the existing level of connectivity between Europe and the UK.”

Figures from Airports Council International (ACI) show that Ireland would be most affected by the change, with 37.4 percent of all air traffic to or from the UK.

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Dublin airport.

Dublin airport.

Ten million passengers travel between Dublin and the UK every year.

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In the event of a hard Brexit, Ryanair chief executive Michael O’Leary said: “We can ground airplanes for a week, two weeks, three weeks. It would be very painful. But we are a big company, we can survive.”

ACI director general Olivier Jankovec claims there will be havoc in airports all over Europe should negotiators fail to strike a deal. Such a scenario would cost hundreds of millions of euro and compromise security, the Irish Times reports.

Irish airline passengers could be stranded if the UK fails to make a Brexit deal.Rollingnews.ie