Flights between the U.K. and Europe could be suspended indefinitely if Britain fails to strike a new air travel deal with the EU within its two year Brexit negotiation period, the chief marketing officer of low-cost Irish airline Ryanair has warned.

Speaking to CNBC Wednesday, Kenny Jacobs called on politicians in both Brussels and London to assert urgency and common sense in making continued air travel arrangements their "number one priority." Failure to do so, he warned, could see airlines unable to fly millions of passengers between Britain and the continent.