Travellers are being warned there will be long delays in European airports this summer, particularly those heading to popular European destinations such as Spain, Portugal, France, Italy and Belgium.

The delays are due to the new European Union rules to combat terrorism in response to the recent spate of terror attacks across the continent. Aviation authorities are required to carry out more rigorous passport checks on travellers.

Tourists have complained of the immigration lines that were “hundreds of metres long” with a wait time of up to four hours.

Lobby group airlines For Europe, A4E, has warned MPs that delays could worsen in the coming weeks as the new regulations have not been fully implemented.