Unions reacted angrily yesterday after British Airways asked its 40,000 staff to work without pay for up to a month in what the airline’s chief executive called a “fight for survival”.

Willie Walsh’s plea for staff to work free for between one and four weeks, which experts say is a first for a British public company, came in the week after he announced he would not take a salary in July. This will save BA £62,000, based on his basic salary of £743,000.

However, staff and unions said that it was much easier to take a pay holiday when your salary is a big multiple of many of your employees. One BA cabin crew member said: “We are treating it like a joke. It’s all very well for Willie Walsh, but my basic is £11,000 a year.”

Mick Rix, national officer for aviation at the GMB union, said: “Until BA executives accept change to their remuneration and bonuses, I would find it difficult to assume most staff would take this request seriously.”

A spokesman for Unite, the trade union, said: “Willie Walsh can afford to work for a month for free, but our members can’t.”

The request for staff to work unpaid came after an earlier cost-saving initiative encouraging staff to work part-time or take unpaid leave of between a month and a year. More than 1,000 staff have signed up for these schemes since they were introduced in May.

BA made a £401 million loss in 2008, its biggest in 25 years. Passenger numbers for the year to March 31 fell by 4.3 per cent to 33.1 million, as the fuel bill rose 44.5 per cent to £3 billion.

Mr Walsh has a deadline of June 24 for volunteers for unpaid work. Salary deductions would be spread over three to six months where possible.

BA denied that staff who volunteered for unpaid work would be given preference if the airline made compulsary job cuts. It has lost 2,500 jobs since last summer and is thought to want 4,000 more.

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