The leader of the Unite union which represents British Airways' cabin crew says the airline is being "vindictive", on the eve of talks to avert strikes.
Tony Woodley, the joint head of Unite, said the two sides had reached agreement in principle on pay and other matters.
But disagreement remains over travel perks for those who went on strike and disciplinary action against some staff.
BA said it was doing its best to resolve the dispute.
Four five-day walkouts are due to begin next week, but talks are due at the conciliation service, Acas, on Monday.
The company said in a statement: "We have made a very fair offer to Unite, which meets the concerns raised over 15 months of negotiations and ensures existing BA crew remain the best rewarded in the UK airline industry.
Also scheduled for Monday is a High Court bid by BA to try to stop the action going ahead and meetings by both parties, separately, with the Transport Minister, Philip Hammond.
Suspension and sacking
Mr Woodley said the union and BA had settled the original dispute - over pay, jobs and working practices, including staffing levels on flights.
But, he said, the dispute was being prolonged because BA was refusing to fully restore travel concessions to staff who went on strike in March, and over the suspension and sacking of over 50 cabin crew.
Mr Woodley said BA chief executive Willie Walsh was pursuing "vindictive" action against those who went on strike by taking away the travel concessions.
He said: "This is not about restructuring any more - it is about taking out activists at the expense of the travelling public. Settling this dispute now would not cost BA a single penny."
BA said a small number of staff had been disciplined - but not because of their union activities.
"British Airways has not suspended anyone for going on strike. To date, of 27 individuals investigated after allegations (mainly of bullying and intimidation), 20 have returned to work - five without any action taken against them and 15 after written warnings. "Seven have been dismissed for serious cases of misconduct."
It said it was trying to work with the union: "We recognise the importance of and continually seek to pursue constructive relationships with our unions."
Mr Hammond said: "I understand how difficult it can be when people's jobs have to change, but a prolonged series of strikes will weaken the company and put those jobs at risk."
The two sides have been in dispute for over a year over cost-cutting plans, including staff reductions on flights.
Unite held seven days of action in March and recently ran an online ballot of its members which resulted in rejection of an offer by BA aimed at resolving the dispute.
The union recommended rejection of the deal because BA had not fully restored travel concessions taken away from those who went on strike in March, and because dozens of staff have been suspended.
Unite has said there was a turnout of 71% of the cabin crew it represents, and 81% voted against BA's offer, details of which have not been revealed.