Airlines including Easyjet and Wizz Air have cancelled dozens of flights as UK air travel disruption continues.
Easyjet said it had cut 80 flights on Sunday, and apologised to customers for the disruption.
Transport Secretary Grant Shapps told the BBC the aviation industry cut too many jobs during the coronavirus pandemic and it must not oversell flights.
He said he wanted airlines to automatically compensate passengers.
Passengers have faced a raft of UK flight cancellations causing disruptions for many families on half-term holidays.
Easyjet said it had cancelled about 80 flights on Sunday "due to the ongoing challenging operating environment".
"We are very sorry and fully understand the disruption this will have caused for our customers," the airline said, adding it was doing everything possible to get passengers to their destinations.
It said it had extended its customer service opening hours from 07:00 to 23:00, and was helping those affected find hotel accommodation.