Frontline health care workers reached a tentative agreement with health system Kaiser Permanente, a move that could bring to an end what unions called "the largest healthcare worker strike in U.S. history."

The announcement, made early Friday morning by the Service Employees International Union-United Healthcare Workers West on social media, said that the frontline workers from the Coalition of Kaiser Permanente Unions were "excited" to announce the tentative agreement. The statement also expressed gratitude to acting U.S. Labor Secretary Julie Su for her role in the negotiations.

Details of the agreement were not yet available, but President Joe Biden hailed it as a "critical step towards securing the pay, benefits, and working conditions these heroes deserve."

"We owe a tremendous debt to health care workers and the hard-working men and women who make their work possible," Biden said in a statement. "I’m grateful to Kaiser Permanente and the Coalition of Kaiser Permanente Unions for coming together in good faith to ensure these workers can continue caring for our neighbors and loved ones. Health care workers and support staff kept our hospitals – and our nation– going during the dark months of the pandemic. They had our backs during one of our nation’s toughest times. We must continue to have theirs."

Biden also shared kind words for Su, his pick to lead the Labor Department on a permanent basis whose nomination has stalled in the Senate.

"This isn’t the first time Acting Secretary Su has helped essential workers and their employers reach an agreement," the president said. "She continues to play an integral role helping my administration and workers across this country build an economy that works for everyone."

"I always say that collective bargaining works. It works for UPS drivers and dock workers, writers, and millions of American workers who exercise their right to participate in a union," Biden continued. "I’m heartened to see health care workers and their employers take this critical step towards securing the pay, benefits, and working conditions these heroes deserve."

Over 75,000 workers picketed for three days earlier this month, advocating for better pay and better working conditions after three years on the frontlines of fighting the COVID-19 pandemic. The thousands of housekeepers, respiratory therapists and other non-doctor staff walked off the job to protest what they said are unsafe staffing levels, labor law violations and inadequate wages.

On Monday, the Coalition served Kaiser Permanente with an official notice that it may conduct a follow-up strike for one week starting November 1, the day after a contract covering Kaiser frontline workers in Seattle expires, allowing an additional 3,000 staff to join the picket lines. 

The Coalition representing 11 healthcare worker unions has been negotiating with Kaiser since April to improve understaffed hospitals and clinics that they say are leading to long wait times, mistaken diagnoses and patient neglect. The group’s four-year contract expired September 30. Negotiations resumed on Thursday.

Kaiser, one of the nation’s largest nonprofit medical organizations, serves 13 million people at 39 hospitals in seven states.

Spectrum News' Susan Carpenter contributed to this report.