Several major international airlines began cutting back flight schedules yesterday in anticipation of a war in Iraq while other carriers said they were prepared to put contingency plans into action as soon as hostilities begin.

British Airways announced that it would suspend daily service between London and Kuwait beginning today. It also said it was closing its three offices in Kuwait City and will cut back its twice-daily service between London's Heathrow Airport and Tel Aviv to once a day. Swiss International Air Lines said it would reduce its flights from Zurich to Cairo from six to two a week. Continental Airlines, which had already reduced the frequency of its flights from Newark to Tokyo, also announced plans to cut back flights to London from Newark, Houston and Cleveland, and to Paris from Newark, beginning next month. Continental left its daily nonstop flight to Tel Aviv unchanged.

Korean Air, Thai Airways International and other Asian airlines have begun cutting services to the United States, Europe and the Middle East, while other carriers said they may act when war begins.

"We haven't canceled any flights, but if the shooting begins, we're prepared to bring our schedule down by 10 to 12 percent," said Joe Hopkins, a spokesman for United Airlines. "We'll maintain all our destinations, but reduce our frequency."

The moves by the jittery airline industry reflect fears that a war in Iraq could push the struggling industry further into financial turmoil. The U.S. airline industry has lost $18 billion since Sept. 11, 2001, and is projected to lose $6.7 billion this year even without a war in Iraq, according to the Air Transport Association (ATA), which represents the industry.

Airline bookings have already fallen off in anticipation of war, although some airlines said that travel during spring breaks had provided a slight boost. Transatlantic traffic has been hit the hardest. According to ATA spokesman Michael D. Wascom, travel on those routes is now off by about 13 percent and is headed downward.

Henry H. Harteveldt, an analyst with Forrester Research Inc., said, "I expect within the next 24 hours we'll see airlines announcing major cutbacks in their transatlantic flying." He said the cutbacks may reach as high as 20 percent.

Airlines have said they will waive rebooking fees for travelers who want to postpone travel once armed hostilities break out in Iraq or if the United States raises its terror alert status to red, the highest level. Harteveldt said travelers should go to extra lengths, including providing cell-phone and pager numbers to airlines and travel agents, so they can be reached if flights are rescheduled or cut.

In a measure of the downturn already underway, OAG Worldwide Ltd., which collects and publishes the schedules of 900 airlines, said earlier this week that worldwide flight schedules were up only 1 percent in the first quarter of 2003 compared with a year earlier. In the final quarter of 2002, by contrast, flight schedules were up 5 percent from the year-earlier period. Another sign of customer wariness is that travelers are booking their flights closer to travel time than they typically had in the past. Orbitz spokeswoman Kendra Thornton said that in March of last year only about 20 percent of travelers using that service booked their flights within 30 days of their trip. So far this month, that percentage has increased to 41 percent.

And airlines are as wary as travelers. "We haven't canceled any flights, but we will be very closely monitoring the situation in the days ahead," said Todd Burke, a spokesman for American Airlines.