Talks between the workers' unions and the telecom giant, however, have stalled. No new bargaining sessions have been scheduled, representatives on both sides said Sunday.

The impasse centers on Verizon's desire to make changes to its workforce and stay competitive as more and more Americans leave landline phones behind. But the unions contend the company makes billions of dollars in profits each year and wants to eliminate job security and increase workers' health care costs.

The contracts that expired were for employees who provide landline service and FiOS Internet in nine states, including Pennsylvania, New Jersey and Delaware, and make up about 3,800 workers in the Philadelphia region alone. Wireless workers are not involved.

One of the landline workers' unions, the Communications Workers of America (CWA), said last week that 86 percent of members had approved of a strike in a recent poll. The company has said that its services would continue unaffected if employees walked out.