Crippling strikes by British Airways cabin crew will deal a major blow to Scotland’s Christmas and New Year celebrations.

Thousands of festive travellers will be forced to make alternative arrangements after staff voted overwhelmingly for industrial action in a move that will

paralyse the UK’s largest airline over one of its busiest periods.

Flights will be grounded for the 12 days from December 22 to January 2, sparking chaos for tourists trying to attend Hogmanay events in Edinburgh and Glasgow as well as people travelling to spend the festive period with their families.

More than 90% of staff gave their backing to the strikes, which they have described as a last resort in a long-running and increasingly bitter dispute over changes to working practices, a pay freeze and job cuts.

Len McCluskey, assistant general secretary at the trade union Unite, said the strength of feeling among workers could push BA into reopening negotiations. He said: "More than nine out of 10 staff are saying that what is happening is wrong -- they want to be treated with dignity and respect.

"We have taken this decision to disrupt passengers with a heavy heart and we are hoping that the company can still avoid it happening. We would like passengers to be angry with the company. It is something of an irony that the people responsible for making BA the best airline in the world are now engaged in a dispute."

The strike will involve around 13,500 employees, roughly one third of BA’s entire staff.

The firm is already losing about £1.5 million every day after a downturn in the industry, but the walkout next week could cost it hundreds of millions. A BA statement described the vote as "cynical", and said it would hurt passengers first and foremost.

"British Airways is extremely disappointed that Unite is planning massive disruption for hundreds of thousands of our customers over the Christmas and New Year holiday period," a spokeswoman said.

"A 12-day strike would be completely unjustified and a huge over-reaction to the modest changes we have announced for cabin crew which are intended to help us recover from record financial losses. Unite’s cynical decision betrays a total lack of concern for our customers, our business and other employees within British Airways."

The airline said it had been forced to reduce the number of staff working some routes by one or two, but that Unite officials had exaggerated the impact of this.

Once benefits are taken into account, cabin crew staff earn between £18,000 and £56,000 a year.

Frances Tuke, spokeswoman for travel industry body ABTA, warned that travellers could struggle to find alternative flights due to the lateness of yesterday’s announcement, and that tour operators would be forced to offer refunds to thousands of customers.

Those who booked their flights after November 2, when the ballot was announced, will be left "high and dry", according to a leading booking website.

Bob Atkinson, a spokesman for travelsupermarket.com, said: "It’s an incredibly sad day for the BA brand.

"It’s 12 years since BA staff members have taken direct action and while they may believe they have a strong case in their disagreement with BA, the real losers here are the everyday leisure and business customers who will have their Christmas and New Year plans disrupted."