Thousands of health care workers at Kaiser Permanente facilities in US states Oregon and California gave a green light Monday to call a strike should contract talks fail.
Sticking points in negotiations appeared to be staffing levels and wages for nurses and others who have been on the front line of the pandemic.
"Health care workers are facing record levels of burnout after 20 months of the COVID-19 pandemic," said Michael Barnett, president of the United Steelworkers local in Southern California.
Some 31,000 of the group's members who work at Southern California Kaiser Permanente locations voted by an overwhelming majority to authorize union leaders to call a strike, according to a USW statement.
The USW along with the United Nurses Associations of California/Union of Health Care Professionals represent the workers.
Nearly 3,400 workers at the major US provider's facilities in Oregon have also voted by a large majority to strike, according to the Federation of Nurses and Health Professionals there.
"This is an unprecedented strike authorization vote, showing total unity amongst Kaiser workers to stage a strike over issues like safe staffing, patient care, and a fair contract," the federation said.
With strikes authorized, elected union leaders can tell workers to walk out at any time, but must provide 10-day notice to Kaiser.
The Oregon federation of nurses said it was part of a 21-union alliance of health care workers, many of which have also authorized strikes.
"We urge Kaiser Permanente management to come to the table and bargain a fair contract that addresses chronic understaffing and safety issues rather than forcing workers into a labor dispute by insisting on dangerous cost-cutting measures," Barnett said in a release.
Kaiser senior vice president of human resources Arlene Peasnall said the health care provider is committed to settling contract negotiations quickly and fairly.
"We ask that our employees reject a call to walk away from the patients who need them," Peasnall told AFP.
"In the event of any kind of work stoppage, our facilities will be staffed by our physicians along with trained and experienced managers and contingency staff."