New minister of police Fikile Mbalula on Tuesday said violence will not be tolerated during Wednesday's National Day of Action.
Thousands of people, including members of opposition parties, civil organisations and others, are expected to march from Church Square in Pretoria to the Union Buildings.
South Africans have been protesting for President Jacob Zuma to resign following his dramatic Cabinet reshuffle which saw the axing of former finance minister Pravin Gordhan and his deputy Mcebisi Jonas.
Mbalula, who was the minister of sport and recreation before the reshuffle, replaced Nathi Nhleko.
Since the reshuffle South Africa has been downgraded to junk status by two ratings agencies.
Mbalula commended last Friday's peaceful marches and said he expected the same on Wednesday.
Co-operation urged
"Who am I to influence marches? I cannot stop people, even if I were to, I would be held accountable," he said when asked if he was not conflicted because he was a member of the ANC.
He said during the anti-Zuma marches last week, people obeyed the laws, did not damage property and exercised their rights responsibly, however, there were sporadic incidents of violence, particularly in KwaZulu-Natal.
He also commended the police for the manner in which they conducted their duties.
"For the march planned for 12 April 2017, we have been informed that authorisation was granted to opposition parties, the convenors."
For the march to be successful, he said, the police need to work with communities.
"Again, government urges protesters to exercise their rights in accordance with the law, without resorting to violence, criminality and damage to property.
"We call upon protest organisers to ensure that the protest actions are peaceful and do not infringe on the rights of others. Intimidation of South Africans who choose not to join the protest will not be tolerated."
He said the police will act against the destruction of property and intimidation.
"Our job is to maintain law and order."
Happy birthday
Last week about 70,000 people participated in a number of marches around the country, but it was not clear how many were expected on Wednesday. The police predicted a turnout of about 10,000.
Acting National Police Commissioner Kgomotso Phahlane said the police were not aware of any counter marches taking place on Wednesday, however if there are, the police will act against illegal gatherings.
He said the gathering outside Luthuli House last Friday was not a march.
"We are looking forward to a peaceful march," he said.
On the sidelines of the briefing Mbalula wished President Jacob Zuma a happy birthday for Wednesday.
"Ukhule ungakhokhobi Nxamalala, sikugadile, siyibambile, [May you grow and stay strong Nxamalala, we are keeping watch over you, we are dealing with it]", he said.
Zuma turns 75 on Wednesday.