Unions are pledging to fight plans by British Airways to cut £37m from workers' pay.
The airline, which is trying to reduce spending in the aftermath of the US terrorist attacks, is proposing not to pay an annual bonus.
It is equivalent to one weeks' pay, and to withhold incremental pay increases next year.
The proposed cuts would affect 36,000 non-managerial staff, including cabin crew, engineers and administrative staff, all based in the UK.
The company's executives agreed last month to a 15% pay cut, while managers have seen their pay reduced by 10% in recent weeks.
BA chief executive Rod Eddington said: "These proposals are not made lightly but are an essential part of what we need to do during this very difficult period."
Mr Eddington said he was very grateful for the hard work staff at BA were putting in, in the wake of the difficulties faced by the aviation industry.
But Ed Blissett, an official of the GMB Union vowed to fight the proposal.
"Senior managers can afford to take a pay cut when they are earning hundreds of thousands of pounds a year.
"It is a different story for our members, some of whom earn as little as £8,000. They cannot afford to reduce their pay."
Unions plan to consult with members before deciding their next move.