Ellen Anreder, a spokeswoman for the United Food and Commercial Workers, said talks have continued after a three-day notice period required before calling a strike elapsed early Sunday night. The union has told its members to return to work, she said.
"As long as there are negotiations ongoing, we will stay at the table," Anreder said. "Being at the table is better than being on the street."
Some 62,000 grocery employees have been working without a contract since March, while in discussions with negotiators for The Vons Cos. Inc.; Ralphs Grocery Co., a subsidiary of The Kroger Co.; and Albertsons, owned by Supervalu Inc.
The union distributed picket signs Sunday as time ran out, and workers held a candlelight vigil outside a Los Angeles grocery store in hope of a new offer.
A four-month strike and lockout that began in 2003 cost Ralphs and other grocery chains an estimated $2 billion.
Grocers said they were hopeful new terms for a contract could be reached soon.
"We think that progress has been made," said Kendra Doyel, a Ralphs spokeswoman. "We're going to stay there (negotiating table) until a contract is settled."
Ralphs has indicated it would initially close all of its stores if there were a strike; Albertsons said it could shutter up to 100 of its locations, while Vons said its stores would remain open.
Los Angeles Mayor Antonio Villaraigosa urged negotiators to find a solution.
"At a time of persistently high unemployment, poverty and foreclosures the last thing we need is a devastating strike that will make it more difficult for thousands of workers to put food on the table for their families, pay their mortgages and afford other basic necessities," Villaraigosa said in a statement issued just before the deadline. "I urge both sides to reach an agreement to avoid a costly and damaging strike."
Both sides in the current dispute announced in July that they had reached a tentative agreement on the employers' contributions to pension benefits, but payments to the union health care trust fund remained a major sticking point.
Union members voted overwhelmingly to reject the health care proposal offered by the chains and to authorize their leaders to call a strike.
Union officials said they were responding to what they characterized as the chains' delaying tactics when they issued the required 72-hour notice Thursday evening to cancel the contract extension under which they had been working.