The leader of the union representing British Airways cabin crew said that last ditch talks gave an opportunity to avert a series of strikes but only if the airline's chief executive changed his "petty, vindictive" attitude.

Tony Woodley, joint leader of Unite, will meet Willie Walsh at the conciliation service Acas in a bid to head off 15 days of strikes from Monday which will cost the airline up to £100m (€110m).

Woodley said the BA chief executive was wrong to say Unite's leaders could not deliver a deal because of the militancy of its cabin crew branch Bassa.

"The deal on the table has been rejected by union members - and I recommended that rejection - because of the petty, vindictive attitude of the company.

"Mr Walsh says that we cannot deliver a deal. He is right about that because the deal on the table cannot be delivered so he has got to change."

Woodley maintained an agreement could be made without costing BA any money but said Walsh had to resolve the row over disciplinary action taken against scores of union members and will have to fully restore travel concessions to staff who took part in an earlier strike in March.

Acas chief conciliator Peter Harwood said the weekend offered "a window of opportunity" to reach a settlement.

He said: "If an agreement is not reached this weekend, there is every possibility that additional pressures on both sides will ensue, which will make a final resolution more problematic."

Walsh has accused the cabin crew union Unite of being "out of touch with reality".

BA reported record losses of £531m on Friday as it worked on contingency plans to deal with the first of a wave of fresh strikes.

The airline was battered by the recession, a harsh winter and seven days of strikes in March.