SAN ANTONIO — The union representing 102,000 employees of SBC Communications Inc. said Wednesday it would stage a four-day strike starting Friday because of a deadlock in contract negotiations with the nation's second biggest local phone company.

SBC's 13-state coverage area includes Texas, California, Illinois, Michigan, Ohio and Connecticut. Among the workers planning to strike are telephone operators, customer service representatives, linemen and other technicians.

"This is an opportunity for the company to see how seriously we are taking this," said Candice Johnson, a spokeswoman for the Communications Workers of America.

CWA president Morton Bahr said the union opted for a short strike to get its message across without doing too much harm to SBC.

"We know that a prolonged strike could cause a loss of major customers and do significant damage to the company," Bahr said. "Hopefully that can be avoided."

In a statement, SBC said it was disappointed by the strike decision. The company says its offer would keep union wages and pensions among the highest in the telecom industry, and that it has yielded to other CWA demands.

"At some point, the CWA must take 'yes' for an answer," SBC said. "For the sake of our customers and our employees, we hope that day is near."

SBC said it will launch its strike contingency plans, which call for managers, contract workers and some retirees to handle key duties in case of a walkout.

It would be CWA's first strike against SBC since a three-week action in 1983. The union has criticized the company for its positions on wages, health care costs and job security.

With less of SBC's revenue coming from local phone service, the union wants its members to have access to positions in SBC's growth areas, among them Internet support, wireless data service and call centers.

Outside contractors, including those with workers in low-wage overseas locations, now handle most of that work.

SBC chief executive Edward Whitacre said in a Wednesday e-mail to employees that CWA workers would be considered for those jobs if the union's cost structure was similar to that of the outside contractors.

"How can we compete with someone making a dollar an hour in India or the Philippines?" asked Ralph Cortez, president of Local 6143 in San Antonio. "These jobs were created in America."

The contract expired in early April. Negotiations have been continuing in Washington with a federal mediator. But for the past three months, health care costs and job security issues have been sticking points.

SBC has proposed a 4 percent lump-sum payment to workers in the first year of its proposed five-year deal, with annual base-pay increases of at least 2.25 percent in the next four years. But the company also wants workers to make higher medical co-payments.

Johnson said the lump-sum amount would not be added to workers' base pay, which will save SBC an estimated $1 billion over the next four years.

"You don't then shift health care costs to workers," she said. "Use some of those savings to offset health care cost increases, which is only fair."