British Airways has started legal action in an attempt to halt the 12-day strike planned by its cabin crew over the Christmas holidays.

BA is commencing legal action in an attempt to protect customers from the massive stress and disruption threatened by Unite's decision to call a 12-day strike from December 22, BA's chief executive Willie Walsh said in a statement on Tuesday.

The airline called on Unite to call off the industrial action by 1400 GMT (9 a.m. EST) on Tuesday. The union has not done so and BA is now seeking an injunction to prevent the strike going ahead.

BA cabin crew on Monday agreed to walk out from December 22 as part of a dispute over job losses and changes to working practices.

The British carrier wants three quarters of its crew to accept a pay rise of between 2 and 7 percent this year, which will be frozen next year, 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 Heathrow.

Shares in BA were 2.3 percent down at 196.30 pence by 1435 GMT after analysts said the strike could result in the airline losing up to 275 million pounds of revenues.

Virgin Atlantic founder Richard Branson called on the British government to step in to prevent damage to passengers' holiday travel plans in future.

It's obviously extremely damaging to everybody, the company, employees, and most importantly the traveling public, Branson told Reuters.

In this day and age there must be a better way than strikes to resolve differences -- maybe government should try to look at other ways to resolve disputes rather than the old fashioned way that will mess up so many people's lives.

(Reporting by Rhys Jones; editing by Paul Sandle)

($1=.6140 Pound)