Heathrow airport's call for airlines to stop selling extra summer tickets has been labelled "unacceptable" by Emirates Airlines, which accused management of "blatant disregard for customers".
The west London air hub imposed a cap of 100,000 passengers per day earlier this week to try and reduce long lines, cancellations, and baggage retrieval delays, calling for airlines including British Airways, Emirates, Virgin Atlantic and others to further cut the number of flight departures.
Emirates is refusing to comply despite what it claims is Heathrow's threat of legal action.
After New York, Dubai is Heathrow's second-most popular departure destination.
Recent weeks have seen labour shortages and supply disruptions hamper the airline industry, with BA, part of International Consolidated Airlines Group SA (LSE:IAG), already cancelling 650 flights for July as part of the government 'amnesty'.
Emirates, one of the world's largest long-haul carriers, said: "LHR chose not to act, not to plan, not to invest. Now faced with an 'airmageddon' situation due to their incompetence and non-action, they are pushing the entire burden – of costs and the scramble to sort the mess - to airlines and travellers."
"The shareholders of London Heathrow should scrutinise the decisions of the LHR management team," it added.
Heathrow's 36-hour deadline for capacity cuts "appears to have been plucked from thin air," Emirates said, adding that the airport's communications "not only dictated the specific flights on which we should throw out paying passengers, but also threatened legal action for non-compliance. This is entirely unreasonable and unacceptable, and we reject these demands."
Emirates said its ground handling and catering staff at London Heathrow, run by the company's subsidiary dnata, are "fully capable" of handling their flights, and therefore, "the crux of the issue lies with the central services and systems which are the responsibility of the airport operator."
As one of Emirates Airline's busiest routes, London-Dubai flights - six a day since October 2021 - have consistently had high bookings for the past 10 months.
Emirates noted Heathrow should have anticipated this. "Now, with blatant disregard for consumers, they wish to force Emirates to deny seats to tens of thousands of travellers who have paid for, and booked months ahead, their long-awaited package holidays or trips to see their loved ones," it added in the statement.
Noting it's a peak time for UK holiday travellers desperate to travel after two years of pandemic restrictions, the UAE airline said 70% of its passengers fly from Heathrow to visit loved ones in far-flung destinations, so new onward connections will not be possible.
"Until further notice, Emirates plans to operate as scheduled to and from LHR," Emirates added.
Responding to the charge, Heathrow spokesperson said the aviation network "continues to face Covid-related challenges," with a key issue being "airline ground handling teams that are only resourced up to 70% capacity to serve passenger demand."
The company says passenger demand is now at 85% of pre-pandemic levels.
"For months we have asked airlines to help come up with a plan to solve their resourcing challenges, but no clear plans were forthcoming and with each passing day the problem got worse," the LHR statement said.
The spokesperson added LHR's 100,000 cap for departing passengers is still higher than the 64,000 cap in place at Amsterdam's Schiphol Airport, ranked the world's busiest airport by passenger traffic in 2021.