Staff at St Mungo’s have begun a three-day strike as part of a long-running dispute over pay and conditions.
Members of the union Unite at the homelessness charity have walked out from projects in Bristol, Brighton and London until 11:59pm on Wednesday.
The union says the charity is refusing to cancel plans to remove a junior staffing cap agreement and fears services will be harmed because higher-paid, more experienced staff would be pushed out and replaced by lower-paid junior staff.
It also cites issues with what it calls the charity’s "draconian" sickness and disciplinary policies.
The charity says it is not cutting pay, changing terms and conditions or making people redundant, and strike action is unnecessary.
A Unite spokeswoman said the number of workers who had walked out would not be available until later on Monday.
In a statement, Tabusam Ahmed, regional officer at Unite, said Howard Sinclair, chief executive of St Mungo’s, should “stop blaming staff for his leadership mistakes” and relationships between staff and employers were stretched to breaking point.
"St Mungo's workers have tried their utmost to arrive at a reasonable settlement with their employer and have been rejected at every turn,” said Ahmed.
“For our members the safety of their clients is their number-one priority and they will take strike action with very heavy hearts. But they believe it is the only way to defend the future of St Mungo’s services.
“It is time for Mr Sinclair to stop blaming staff for his leadership mistakes and take responsibility for the breakdown in industrial relations. We were willing to compromise; he was not.”
Sinclair said the charity had “done everything possible” to stop the strike and made compromises.
He said the charity’s main focus was on organisation-wide pandemic planning.
“We want Unite to call off their strike immediately,” he said. “With coronavirus, we know the focus of our staff, union or non-union members, will be even more on the welfare of our vulnerable clients.
“The right to life is more important than the right to strike, and organising pickets and rallies outside, while clients need support in services and when they are rough sleeping, seems incredibly misjudged.”