Thousands of California state workers began a sweeping, one-day strike on Wednesday, with workers set to rally outside government buildings in several cities, as tensions boiled over lapsed contract negotiations with Governor Gavin Newsom’s administration.

SEIU Local 1000, a union that represents roughly 100,000 public employees, including nurses and teachers, has been pushing for higher wages, flexible telework and affordable healthcare.

The union has been at an impasse with the state since its contract expired on 30 June.

SEIU Local 1000’s negotiators say state officials rejected their key proposals: a 20% salary increase over three years, higher state healthcare contributions and flexible telework – Newsom has required state workers to be in office four days a week.

“We are going on strike because we know the Newsom administration can and must do better,” Anica Walls, the union’s president, said in a statement. “They must return to the table and bargain in good faith toward a contract that allows state workers to afford groceries, childcare, rent and other necessities.”

Union representatives also argued in a complaint filed with California’s public employment relations board that the state engaged in bad faith bargaining, by allegedly waiting until 30 June to respond to some of the proposals and saying there was “no money” for additional compensation.

The state has not commented publicly on the status of the contract negotiations, citing confidentiality.

Wednesday’s picketing marked a first for the union.

California’s department of human resources (CalHR) had reportedly attempted to block the strike, arguing the union did not have plans to exempt essential workers and thus was compromising public health and safety. The labor board determined a list of about 5,000 workers deemed essential, according to the union, who will report to work during the strike.

“The department remains focused on achieving a fair and responsible agreement and continues to be available at the bargaining table,” a CalHR spokesperson said in a Wednesday statement.