British Airways extended a halt on ticket sales for some short-haul flights out of London Heathrow airport by another week to Aug. 15, adding to the summer’s travel chaos.

The move comes just a day after the unit of IAG SA imposed a moratorium on sales though Aug. 8, citing daily passenger capacity limits imposed by Heathrow to help cope with a staffing crisis. BA indicated that further suspensions are likely until the end of the summer travel season.

“We’ll continue to manage bookings to be within the Heathrow-imposed cap so we can get our customers away as planned this summer,” a spokesman said in an email. 

Heathrow, which has blamed insufficient airline staffing for delays and upheaval, suggested Tuesday that the situation is being exacerbated by the summer increase in leisure passengers who, rusty about travel rules, are packing liquids in their carry-on bags. That in turn is triggering additional checks which “slow down the flow through security for all passengers.” 

Airlines and airports across Europe are struggling to meet demand that’s rebounding strongly from the coronavirus crisis, with the London hub warning last week that the situation could persist through next summer.

Amsterdam Schiphol, one of western Europe’s four main hubs alongside Heathrow, said Tuesday it’s extending capacity curbs into the autumn, with a cap of 67,500 departing passengers a day in September and 69,500 in October.

The numbers are lower than for August, reflecting slower transit times through security as people hand over coats worn in the cooler weather for inspection, according to the airport, which is home to the Dutch division of Air France-KLM.

British Airways has already canceled about 13% of planned capacity this summer amid a shortfall in its own employees and Heathrow’s limit of 100,000 daily departing customers, imposed on July 12.