US health care provider Kaiser Permanente and unions representing tens of thousands of its staff said Friday they had reached a tentative deal to end what was billed as the sector's biggest ever strike.

The stoppage was the latest labor dispute to rock the United States in a year that has seen workers downing their tools from Detroit to Hollywood.

"We are excited to have reached a tentative agreement with the frontline health care workers of the @UnionCoalition this morning," the corporation wrote on social media.

More than 75,000 members of the SEIU-UHW and other unions walked out last week in a three-day stoppage that chiefly affected Kaiser Permanente's operations in California, Colorado, Oregon and Washington state.

Staff had complained that they were overworked and underpaid, with salaries that were not keeping up with rising prices.

"The frontline healthcare workers of the Coalition of Kaiser Permanente Unions are excited to have reached a tentative agreement with Kaiser Permanente," the SEIU-UHW wrote on social media with a picture that included an all-caps "VICTORY."

The strike added to the drumbeat of discontent that has seen workers all over the country down tools.

American consumers are battling inflation and a cost-of-living crisis that is shrinking real pay packets as prices for everyday staples like gas, groceries and rent continue to rise.

Inflation is a global problem driven by the complex interactions of strung-out supply chains, geopolitics and the after-effects of the Covid-19 pandemic.

But its effects are felt locally -- and voters tend to blame their politicians.

That has created a headache for President Joe Biden, who faces a tough re-election battle next year, likely against populist former president Donald Trump.

Biden's administration has gone to pains to present itself as on the side of workers in a number of labor disputes, and got involved in the spat between Kaiser Permanente and its staff.

Both sides said they were "thankful for the involvement" of acting US Labor Secretary Julie Su.

Biden on Friday welcomed the tentative agreement, and lavished praise on the health care workers who "kept our hospitals -- and our nation -- going during the dark months of the pandemic."

Biden noted the close involvement of Su in the agreement, which he said was not the first time she had helped workers "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," he said.

"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."