ANC leader Jacob Zuma is suing The Guardian for defamation over an article published in March that described his leadership style as "morally contaminated".
He is demanding an apology and damages from the respected British daily, his legal representatives in London, Schillings Laywers, said in a statement on Monday.
It did not specify the sum Zuma is seeking over the article by Simon Jenkins, which ran under the headline "Get used to a corrupt and chaotic South Africa. But don't write it off."
The law firm said "Mr Zuma believes that the published column contains grossly defamatory, false and indefensible allegations, the most serious of which is the false claim that he is a rapist."
It quoted Zuma as saying: "The media should report accurately and honestly. It is not fair that they should print lies, distort or exaggerate issues merely for the sake of sensationalism and increased revenue.
"How can they be allowed to damage a person's reputation in this way? The world needs a media that all people can rely on, even in the United Kingdom. In this matter I was obliged to act where I had been wronged."
Shillings Lawyers said the article has been removed from The Guardian's website.
It had warned that those "dealing with South Africa must probably get used to Zuma's style of government - morally contaminated, administratively chaotic and corrupt," and quoted an unnamed friend of the author describing Zuma as "a criminal and a rapist".
Zuma, who is expected to become president after next week's elections, is also suing local satirist Jonathan Shapiro, the Sunday Times and its holding company for seven million rand over a cartoon depicting him raping Lady Justice. - Sapa