British Airways' (BA) cabin crew will today begin a vote to decide whether to strike over Christmas as new working practices come into force.

The ballot closes on December 14 and, if staff vote in favour of industrial action, the first strike could start a week later on December 21, affecting vital Christmas traffic.

Unite, the union, is urging the 14,000 cabin crew it represents at the airline to contact employment solicitors with any complaints about the way the new employment rules are working.

Willie Walsh, the chief executive of BA, is proposing a two-year pay freeze for crew, reduced holidays and cuts to the allowances for working on long-haul flights. New employees will start on different contracts without the long-haul bonuses and be paid less.

Of the 14,000 crew affected, more than 3,000 will move to part-time work and 1,000 will take voluntary redundancy.

Unite has set up an e-mail address, with OH Parsons, the employment lawyers, and cabin crew members can use it to log any complaints after the changes. The e-line will serve as a way of collating information for Unite’s legal action against BA, which is due in the High Court on February 1 next year.

Today's vote follows last week's announcement that BA will merge with Spain's Iberia.

The union has said that it will not back the proposed merger between the two loss-making airlines unless it is assured that there will be no more job losses.

Cost-cutting is one of the main reasons behind the £4.5 billion merger, which will create Europe’s largest airline by passenger numbers, carrying 62 million people a year.

The planned new umbrella company, to be known as TopCo, is also facing discontent from workers in Spain. Iberia has proposed a hiring freeze until 2012, a two-year salary freeze and early retirement for cabin crew over 55. In return, Spanish unions have threatened strike action over the proposals and are demanding a 4 per cent pay rise.

Iberia workers are well-paid compared with BA staff, with pilots earning €190,000 (£170,000), well above BA’s average of £107,600. The Spanish pilots also receive a 7.5 per cent bonus every three years.

BA and Iberia will continue to operate as separate airlines under TopCo, which will be incorporated in Spain but have its headquarters and stock market listing in London. If the merger goes ahead, the combined company will be chaired by Antonio Vázquez, the chairman and chief executive of Iberia. BA shareholders will own 55 per cent with the remainder held by Iberia investors.

Mr Walsh, who will lead the combined company after the Iberia merger, gained a reputation as a union-buster and a cost-cutter during his time with Aer Lingus, the Irish airline. He has already has stripped £400 million of costs from BA in the past six months, as it faces competition from no-frills airlines, as well as a decline in demand for business-class travel because of the global economic downturn.

There are still hurdles to the merger with Iberia, including BA’s estimated £3 billion pension fund deficit. Iberia has a get-out clause if BA cannot reach agreement with the trustees of its pension fund on how to deal with the deficit.

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