LONDON - The Unite union will open a strike ballot for BA cabin crew on January 25 after talks with the airline failed to secure a deal on changes to working conditions, potentially prolonging the winter of travel chaos.

The vote is expected to take about a month and, if the almost 13,000 British Airways cabin crew affiliated to Unite agree to strike, a walkout could begin from the beginning of March, Unite said in a statement on Monday.

In its own statement, BA said it was saddened but not surprised that the union had called another ballot.

BA wants three quarters of its crew to accept pay rises of 2 to 7 percent this year and a pay freeze in 2010, and for 3,000 staff to switch to part-time working, along with a reduction in onboard crewing levels from 15 to 14 on long-haul flights from London's Heathrow airport.

Under the package we have put forward, our crew will remain the best rewarded in the UK. There would be absolutely no justification for a strike, BA said.

Snow and freezing weather swept Britain earlier this month causing travel chaos for thousands as rail and air travel were disrupted for almost two weeks.

Shares in BA, which have lost 13 percent of their value in the last three months, were 3.4 percent up at 199 pence by 12:31 p.m., valuing the business at around 2.2 billion pounds.

The union said last month it would move to a new ballot after a planned Christmas strike was ruled unlawful.

We have told (BA) management all along that this dispute, and the damage it does to BA's prospects, can only finally be resolved through negotiation, Len McCluskey, assistant general secretary of Unite, said in a statement.

That remains our position, and I hope the company will make the best use of the time available before the ballot closes.
(Reporting by Rhys Jones and Clara Ferreira-Marques, editing by Will Waterman and Mike Nesbit)