White House spokesman Ari Fleischer told reporters that President Bush was prepared to create an emergency board, if necessary, to try to facilitate a new labor contract.
The International Association of Machinists and Aerospace Workers said earlier Friday it had voted overwhelmingly to strike, if no deal were reached.
The earliest the union could walk off the job is Dec. 21, which is when a mandated 30-day cooling off period expires. But intervention by Mr. Bush would delay that action until mid-February at the earliest.
"The president has made it clear that given the fragility of the airline industry and the importance of the American people's right to travel, he would look very unkindly on any action that would interfere with those rights," Fleischer said.
Machinists spokesman Frank Larkin said 99 percent of the nearly 10,000 votes cast Thursday evening backed a strike. The union represents 15,000 United mechanics.
The mechanics last received a raise in 1994, and their efforts for increased pay have been hurt by an industry slowdown partly blamed on the Sept. 11 attacks.
United spokesman Joe Hopkins said the nation's No. 2 airline does not expect any disruption of service as a result of the vote.
United, which already was suffering through its worst year ever, has said any immediate raise is impossible and has withdrawn its latest contract offer. Hopkins said no negotiations are scheduled, and he didn't know when the two sides might sit down again.
The airline has cut 20,000 jobs and about 750 daily flights since Sept. 11. It lost $1.16 billion in the third quarter and has said it was losing about $15 million daily this fall.
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