The public sector wage bill is not bloated and it is "irresponsible" of Finance Minister Tito Mboweni to announce a plan to address the issue when there is a bargaining process in place to address such matters, Cosatu said on Thursday.
In his Budget announcement on Wednesday, Mboweni unveiled a plan to cut the public sector wage bill of provincial and national departments by R160.2 billion over three years.
Cosatu President Zingiswa Losi lambasted the announcement, saying the public service was struggling with vacant posts, facing critical shortages in nursing, teaching, and police jobs.
"What we are not going to accept is what was attempted by the minister yesterday, to speak about what is not in his competence," said Losi in a media briefing following the federation's central executive committee.
She stressed that in her view, Mboweni could not bring forward issues that must be negotiated when there are collective bargaining processes in place, adding that this undermined the negotiation process.
"There is a minister assigned to that, and you can't undermine that process," she added.
In the Budget Review, Treasury has proposed cuts to the wage bill of R37.8 billion in 2020/21, R54.9 billion in 2021/22 and R67.5 billion in 2022/23.
Losi said Mboweni himself had acknowledged the issue of understaffing among critical services of the public sector, adding that the public service may be bloated from the top.
In June 2018 government reached a three-year wage agreement with civil service employees, which included raises of 6% to 7% for the year through March 2019, and as much as 1 percentage point more than the consumer inflation rate for the following two years.
The federation, which is in alliance with the governing ANC, vowed to escalate the matter with the party.
The country's public sector wage bill has been repeatedly flagged by international lenders and ratings agencies, who have urged the government to cut spending.
On Wednesday, deputy finance minister David Masondo told reporters that government had submitted a proposal to the Public Service Coordinating Bargaining Council on Tuesday to formally table the proposal for discussion with unions, following numerous informal discussions.
The submission showed that other cost drivers in the public service, apart from the wage bill, included corruption and fraud, use of consultants and litigation. It noted the size of government had grown over the past 25 years, and spending as a share of GDP was at its highest since 1994.