British Airways is confirming the equivalent of 1,700 full-time cabin crew posts will disappear by the end of November, but insists the cuts are voluntary.
The airline says around 1,000 cabin crew have indicated they would like to take voluntary redundancy, with a further 3,000 staff looking to switch to part-time working - equivalent to 1,700 full-time posts.
And in a structural change, BA's long-haul cabin service directors will also start to serve passengers on board from the end of next month, meaning that on the carrier's Boeing 747 fleet for example, the total cabin crew will reduce from 15 to 14.
A BA spokesman says the airline is "not required to negotiate on this", although it stresses it is continuing to talk to cabin crew unions with meetings planned next week with the UK's Advisory, Conciliation and Arbitration Service (ACAS).
The spokesman adds the airline is seeking permanent changes and savings, but insists it is not altering contractual conditions.
"This is something going back to us talking to unions from the start of the year - it is another step in that process," says the spokesman. "Some of the way it has been positioned is very misleading."
BA also highlights the recent IATA analysis predicting the aviation industry would make a £7 billion ($11 billion) loss this year, adding it expects to post a "significant" individual loss for the second consecutive year.
"Without changes, we will lose more money with every month that passes," notes a BA statement. "It is essential we make ourselves more efficient if we are to ensure our long-term survival.
"We cannot ignore the fact our Heathrow-based cabin crew costs are much higher than those of our Gatwick-based crew and of our competitors."
Union representatives were not immediately available for comment.