“We will act against forces who are exploiting the concerns of our people about illegal immigration to further their own political, personal or criminal agendas,” he said, cautioning against social media campaigns that spread misinformation and lies about foreign nationals.
He also told South Africans there was “no space for xenophobia, racism, sexism, Afrophobia or any other forms of intolerance in South Africa”.
“Our country – like many others throughout history – is a product of migration. It is the reason for our diversity and contributes to our vibrancy,” he said.
South Africa is home to more than three million foreigners, about 5% of the population, according to official figures – but there are believed to be many more without papers.
During his 30-minute speech, the president pointed to the scale of the problem and how “illegal migration routes increasingly overlap with organised crime”.
“In the past year alone, the Border Management Authority managed to intercept and stop over 450,000 people who were attempting to enter South Africa illegally,” he said.
Ramaphosa explained how unscrupulous employers pay undocumented migrants well below the minimum wage and “merely” pay a fine if caught.
Plans had been launched to hire 10,000 inspectors to crackdown on such businesses and those found guilty would fail tougher penalties “including imprisonment”, he said.