Verizon Communications Inc. said 45,000 striking workers will return to the job beginning the night of Aug. 22, while the two sides keep negotiating what the company called “major issues.” Employee benefits, work flexibility and job security are among the areas that still need to be negotiated, Verizon said in a statement today. Union employees will work, for an undefined period, under terms of the contract that expired on Aug. 6, Verizon said.

Facing a decline in its traditional landline phone business, Verizon has been seeking work-rule changes and employee contributions to health-insurance premiums. Workers have said they shouldn’t have to make substantial concessions as profits rise and executive pay remains healthy.