LONDON - A three-day strike by British Airways cabin crew affecting thousands of travelers began Saturday after last-ditch talks between the airline's management and union leaders collapsed.

The walkout has forced BA to cancel thousands of flights, but it still hopes to operate around 65 percent of its international schedule over the period.

The Unite union has gathered some support from unions in the United States, Germany and Spain for its action - taken to protest a pay freeze and changes to working conditions - but the other unions have so far stopped short of pledging direct action that would affect BA's ability to refuel and service its planes.

A total of 1,100 flights out of the 1,950 flights scheduled to operate during the walkout will be canceled, but the airline has leased planes and crew from rival carriers to take up some of the shortfall.

At its Heathrow base, more than 60 percent of long-haul flights will operate, but only 30 percent of short-haul. At Gatwick, all long-haul flights and more than half the short-haul flights will run as normal.

"Tens of thousands of BA people stand ready to serve our customers," said BA Chief Executive Willie Walsh. "BA will be flying tomorrow."

Adam Huberman of Issta, a flight and tour agency specializing in trips to Israel, said he was taking 60 to 80 calls a day from passengers planning to travel to Israel before Passover, which starts March 30.

He said the strike couldn't have come at a worse time.

"It is the busiest time of the year," he said, adding that the agency had put on some flights of its own. "Some will be able to go but fares are obviously higher because it's so last minute."

Among others whose plans were affected were the Cardiff County and Vale of Glamorgan Youth Band from Wales, who are scheduled to play in a wind band festival at Carnegie Hall in New York on Tuesday.

Their scheduled Saturday flight was one of the ones BA has canceled, but after television and radio appeals - and a letter to rival virgin Atlantic - BA managed to get them onto alternative planes.

Picket lines will be mounted over the weekend at several entrances to Heathrow, but Walsh said he had "no concern whatsoever" about the threat of solidarity actions in other countries.

The U.S. International Brotherhood of Teamsters urged travelers to find alternatives during the strike.

"We are keenly aware of British Airways' operations in the United States and the cities served by the airline," the Teamsters, who represent 40,000 workers in the aviation industry, said in a statement. "We continue to look at this situation as it evolves and are keeping our options open."

Walsh said it was "deeply regrettable" that the union declined to accept a proposal on pay and working conditions from the airline, adding that offer would be withdrawn once the strike begins.

Unite joint general secretary Tony Woodley said that BA "does not want to negotiate and ultimately wants to go to war with this union."

The prospect of travel chaos in Britain in the run-up to the Easter break also intensified with news that railway signal workers voted in favor of a strike, joining rail maintenance workers.