Pretoria - Minister in the Presidency Jeff Radebe was booed as he approached the stage to receive a memorandum of understanding at an anti-corruption march in Pretoria on Wednesday.
Marchers gesticulated for him to go away.
Some blew whistles while others rolled their hands - a soccer signal for substitution.
The crowd drowned out Radebe as he tried to address them.
When he started telling them about the National Development Plan (NDP), they started booing and singing.
In response Radebe told journalists that just as they had the freedom of expression, he had the freedom to convey what government was doing about corruption.
He read from a statement and said the crowd was not going to infringe on his freedom to give his message to them.
Before he addressed the crowd, Economic Freedom Fighters (EFF) leader Julius Malema said, "We are saying to Jeff, if you [are] not going to change your behaviour, your days are numbered."
He said in 2019 the only view Radebe would have of the Union Buildings would be from his television, because in the 2016 local government elections, the EFF was going to give the African National Congress a run for their money.
When ousted Congress of South African Trade Unions (Cosatu) general-secretary Zwelinzima Vavi walked on stage, the crowd started chanting "Vavi, Vavi".