By LOU HIRSH
The Press-Enterprise

Negotiations resumed this week on a contract affecting thousands of Southern California grocery workers at three major chains, but union and store officials are sticking by an mediator's order not to divulge details.

Adena Tessler, spokeswoman for Albertsons, Ralphs and Vons, said Friday the talks will resume again next week.

The United Food and Commercial Workers union did not return calls seeking comment. The union and supermarkets have been negotiating intermittently since February on a new contract that would govern pay and benefits for 65,000 grocery employees at the three chains.

In the Los Angeles area this week, the union launched a "Walk for Respect" campaign, asking people to pledge not to shop at the three grocery chains in the event of a strike or lockout.

According to a union Web site, walks were planned for Friday and today at Albertsons stores in Upland.

In a joint release this week, the grocery chains criticized the action, saying activity outside stores "only serves to frighten our employees and alarm our customers."

While the grocers say talks have made progress on complex issues such as health care, the union contends the stores are trying to put too much of the burden for health costs on workers. That issue prompted the union to walk away from negotiations on May 8, although union leaders announced the very next day that talks would resume.

On Friday, a union leader predicted that any strike would spread beyond the region.

"The battlefield will not just be in Southern California," said Patrick O'Neill, national director of collective bargaining for the union. "It won't be confined to the geography of California if there is a work stoppage."

The union hopes to come to an agreement by the end of next month, O'Neill told Bloomberg News. There's a 40 percent chance of a strike this year , he said.

Current and former Ralphs employees who were locked out of their jobs during a long labor dispute in 2003 and 2004 have until Monday to file claims for part of a $50 million restitution fund created by the grocery company.

Bloomberg News contributed to this report.