Traffic wardens will go on strike from tomorrow in a row over pay, threatening the loss of tens of thousands of pounds in revenue.
Members of Unite and Unison at Southampton City Council will take seven days of strike action in the latest stage of a campaign of industrial action by employees.
Unite officials said the action by traffic wardens will lead to a revenue loss of £100,000.
Refuse collection workers have already taken industrial action and plan another strike on Saturday, with unions warning of a growing backlog of uncollected waste.
Industrial action short of strikes, such as removal of private car use to provide services, overtime bans and working to rule, continues throughout the whole council.
A mass meeting of Unite and Unison is taking place on Thursday, addressed by officials including Unite general secretary Len McCluskey.
Unions say council staff have been told to accept a pay cut, with some care workers said to be facing double-figure cuts of up to 17%.
Ian Woodland, Unite regional officer, said: "Southampton City Council are being extremely cynical in their conduct.
"They know people are terrified about losing their jobs so they are exploiting this as a moment to slash wages.
"We have repeatedly said to the council that there are better ways to make savings. All they have to do is sit down with us to talk about a shared way forward.
"They refuse to do so, preferring instead to bully and terrify workers into accepting an attack on their living standards.
"Some of the poorest paid in the council's workforce are being told 'take a loss of thousands of pounds a year or take a hike to the dole queue'.
"It is little wonder then that they feel that they have no option but to take action."
Andy Straker, of Unison, added: "Council leader Royston Smith knows very well that the way to make savings at the council is to work with the workforce and the taxpayers.
"Instead, he prefers to run this local authority through imposition and threats.
"These are times of tremendous anxiety and hardship for workers in Southampton but they will not be cowed into accepting horrendous pay cuts, particularly when there are other ways that the council, if better run, could save money.
"We are saying to the people of this city, first this council will come for our jobs and wages but next they will come for your services.
"This is the moment to stand up for a better deal for Southampton."