MORE than 50,000 Los Angeles county workers have walked out after talks on a new contract broke down, closing libraries and disrupting administrative operations.

The two-day strike began on Monday evening after the failure of negotiations on a new contract to replace the one that expired in March, according to leaders of the Service Employees International Union’s “local” (branch) 721.

The branch, which represents more than 55,000 workers, including in public health, social work, parks and leisure services and clerical functions, says it is first time all of its members have gone on strike. With 10 million residents, Los Angeles is the most populous county in the United States.

“This is the workforce that got LA county through emergency after emergency: the January wildfires, public health emergencies, mental health emergencies, social service emergencies and more,” said branch leader David Green in a statement. “That’s why we have had it with the labour law violations and demand respect for our workers.”

The union has accused the county of 44 employment law violations during contract negotiations, including surveillance of and retaliation against workers engaged in union activity and contracting out positions represented by the union.

The county says it faces “unprecedented stresses” on its budget, including a tentative $4 billion (£2.98bn) settlement of thousands of childhood sexual assault claims, a projected $2bn (£1.49bn) in costs related to wildfires in January and the potential loss of hundreds of millions of dollars in federal funding.

“We are trying to strike a balance: fair compensation for our workforce while sustaining services and avoiding layoffs in the midst of some of the worst financial challenges we have ever experienced,” spokeswoman Elizabeth Marcellino said in a statement from the chief executive office.

The city of Los Angeles faces similar financial trouble, with Mayor Karen Bass’s recently proposed budget including 1,600 layoffs to ease a nearly $1bn (£746 million) deficit.

More than 150 county workers picketed the Los Angeles General Medical Centre on Monday with signs reading: “We are the safety net!”

Lillian Cabral, who has worked at the hospital since 1978 and is on the bargaining committee, said she was frustrated by a process filled with long delays and little movement by the county.

“It's so unfair to us, it's so unfair to our patients and to our clients and our community,” she added.