Unison bosses have accused the administration of prioritising a mayoral chauffeur over protecting frontline services and improving redundancy payments for staff losing their jobs.
Civic chiefs are due to unveil parts of their revised budget today, after Southampton was given an extra £5m in government funding.
It is the first time the trade unions, who wanted the cash spent on services and improved pay-offs for staff facing compulsory redundancy, have broken ranks with Labour over their handling of the budget.
The unions campaigned heavily for the party during last year’s election, at which Labour swept to power, ending four years of Tory rule in which the Conservatives had pushed through controversial pay cuts for many council staff.
But Unison said today it was “bitterly disappointed” with the choices made in the revised budget.
The union said it was angry at the decision to reinstate £40,000 to the budget to ensure the mayor has a chauffeur and putting £1.6m back into council reserves, while almost 150 full-time-equivalent posts are at risk.
The authority is putting £193,000 back into its youth services, but Unison said a quarter of that cash will go on one manager, whose role will be to encourage community groups to take over council provisions.
The children’s home Our House and the city’s archaeology services will still close, while face-to-face and telephone visitor information services will also be removed.
But the council will put £500,000 into a new fund which council leader Richard Williams can use for investment in projects that will help “get the economy moving”.
Branch secretary Mike Tucker said not all the staffing implications of the revised budget are known at this stage, as the trade unions and staff have not been consulted on all the revisions to the budget: He said: “Unison is bitterly disappointed at the choices Labour councillors have made.
“We still believe that the financial problems the council are in are caused by the Conservative Government and the decisions made by the previous Conservative administration. “But councillors are only saving five jobs in the youth service while at the same time spending £300,000 on employing consultants for three months to develop the “Peoples Directorate” which will include services to young people. “The council is refusing to improve redundancy terms for over 50 long-serving council employees who are facing compulsory redundancy while spending £40,000 to ensure that the mayor gets driven round the City for the next 12 months. “By the choices they have made, Labour councillors have demonstrated that they are at risk of losing touch with the people of Southampton who put them in office in May 2012.”