Verizon worker PJ Foley, center, of Quincy, Mass., leads a chant while picketing outside of the Verizon's New England headquarters in Boston, Sunday, Aug. 7, 2011. Forty-five thousand Verizon Communications Inc. workers from Massachusetts to Washington, D.C., went on strike Sunday after negotiations fizzled over a new labor contract for more than a fifth of the company's work force.

NEW YORK — Stalled contract negotiations led thousands of workers in Verizon Communication’s wireline division to go on strike Sunday, potentially affecting landline operations as well as installation of services like FiOS, its fiber-optic television and Internet lines.

The contract for the 45,000 employees from Massachusetts to Washington, D.C., expired at midnight Saturday with the company and the workers unable to come to terms on issues including health care costs and pensions.

Verizon offers landline service in Connecticut, California, Delaware, the District of Columbia, Florida, Maryland, Massachusetts, New Jersey, New York, Pennsylvania, Rhode Island, Texas and Virginia.

The dispute does not affect the company’s wireless division. Verizon is the nation’s largest wireless carrier.

Verizon employees who are members of the Communications Workers of America union picketed headquarters in New York City on Sunday morning, wearing red and holding signs with messages including “CWA on strike for middle-class jobs.”

Vinnie Galvin, 56, said Verizon workers are the backbone of the industry. “They're trying to bust us. ... This is stuff that it took us 40, 50 years to get.”

The company is asking for changes in the contract because it says its wireline business has been in decline for more than a decade as more people switch to using cellphones exclusively. It had 25 million landlines at the end of the second quarter, down from 26 million at the end of 2010. It has been selling off some of its landlines to other phone companies.