SAN ANTONIO ? The union that represents 102,000 employees of SBC Communications Inc. is poised to tell the nation’s No. 2 local phone company that it will strike over job security, health care and other issues.

The Communications Workers of America on Tuesday delivered 24 hours’ notice of a strike against San Antonio-based SBC amid faltering negotiations for a new contract. The notice would allow SBC workers to strike beginning at noon today. The contract under negotiation covers about 100 workers in the Lawrence area.

The union’s membership approved a strike authorization vote last month, but CWA officials promised SBC they would give 24 hours’ notice of a walkout in exchange for a company guarantee to provide health benefits in event of a strike.

In the statement on the union’s Web site, CWA President Morton Bahr said the notice was “because the company has failed to respond in an effective way to our members’ key issues, especially in the areas of job security and access to jobs of the future.”

The union opposes cuts to its medical benefits and wants more job-security guarantees. Since late 2001, SBC has cut about 30,000 jobs, or about 15 percent of its work force, in an aggressive move to reduce its operating costs.

The union has urged SBC to give the workers it represents in 13 states a chance to transfer into growing areas such as providing high-speed DSL service if their old jobs come under the budget knife. The CWA negotiating team remained in Washington, D.C., ready to continue talks at a federal mediator’s call.

Walt Sharp, an SBC spokesman, said the company also wanted to keep negotiating.

“We do believe progress is being made, and we intend to pursue additional discussions with the union,” Sharp said. “We think we have an excellent proposal on the table, and we’re going to continue working it.”

In three months of negotiations to reach agreement on a new contract replacing the pact that expired April 3, health care costs and job security issues have been sticking points. The company wants to keep medical expenses down and has proposed making employees pay more for coverage. Health care costs at SBC are rising at 14 percent a year and now top $3 billion, the company says.

The company had made a new contract proposal Friday. But Bahr, in a prepared statement on the CWA Web site, said it was an “extreme disappointment,” adding, “Such unresponsiveness after so many weeks of bargaining shows disrespect for our members and our union.”