The European Commission announced its intention to return to the longstanding 80-20 slot use rule, which requires airlines to operate at least 80% of every planned slot sequence.

While airlines are keen to restart services, Iata said the "failure of several key airports to accommodate demand, coupled with increasing air traffic control delays," means a premature return to the 80-20 rule could lead to further passenger disruption.

"The chaos we have seen at certain airports this summer has occurred with a slot use threshold of 64%," said Iata’s director general Willie Walsh.

"We are worried that airports will not be ready in time to service an 80% threshold by the end of October. It is essential the Member States and Parliament adjust the Commission’s proposal to a realistic level and permit flexibility to the slot use rules.

"Airports are equal partners in the slot process, let them demonstrate their ability to declare and manage their capacity accurately and competently and then restore the slot use next summer."