(AP) -- Union workers at AT&T are giving their leaders the authority to call a strike as part of negotiations for a new contract covering 112,500 employees.

Several contracts covering at the phone company's landline division expire on April 4. AT&T Inc. is trying to make the employees pay more for their health care, among other concessions.

The Communications Workers of America says 88 percent of members covered by the contracts voted in favor of a possible .

AT&T spokesman Walt Sharp says the strike authorization is "expected and routine at this stage in the negotiations." AT&T is the nation's largest employer of union labor.

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