NEW YORK — A federal judge blocked Northwest Airlines flight attendants from going on strike yesterday, handing a victory to the airline just hours before a planned strike action that could have devastated the cash-strapped company.

U.S. District Judge Victor Marrero said he will issue an injunction to allow time for him to examine the case. He said Northwest Airlines Corp. made a "persuasive case" that a delay in any strike was necessary so that the legal issues could be resolved.

He said that while the injury to flight attendants would be to delay their ability to strike, "far greater injuries exist to Northwest and the public by permitting the strike to commence at this point."

The flight attendants had planned to launch unannounced, sporadic walkouts anytime after 4 p.m. Hawai'i time yesterday. Northwest, already operating under bankruptcy protection, has said a strike could kill it.

The nation's fifth-largest airline, Northwest has about 7,300 active flight attendants. The workers are angry the company imposed 21 percent pay cuts, which they say amount to 40 percent when health insurance increases are added in, as well as work rules they had rejected.

Northwest has said it needs $195 million a year in savings from flight attendants, who have twice voted down tentative agreements. After the latest vote on July 31, Northwest imposed the pay cuts with the permission of a bankruptcy judge.

Marrero urged the parties to resume negotiations and said he will give them until Wednesday to tell him whether fruitful talks are possible. If not, he said, he will decide the case at a date that was hard to predict "given the complexity of this matter."

The case involves obscure labor law provisions. A key question, however, is: Can airline employees walk off the job after management unilaterally cut their pay and changed their work rules?

While the union has maintained that firing those who strike would be illegal, striking is illegal under the injunction. There were no apparent plans among union members to do so until the judge has decided the case.

The Association of Flight Attendants said Marrero could make a final decision next week.

"Management and the courts can stall us, but they cannot defeat us," said Mollie Reiley, interim president of the union's Northwest branch.

She said the union would continue to prepare for job actions.

"Something is terribly wrong when a company that just made a quarterly operating profit of nearly $200 million continues to insist on the same cuts it demanded from flight attendants when it was losing money."

Flight attendant Lou Rudy asked outside court: "When does it end? When does the company have to negotiate?"