Jacob Zuma has resumed his campaign to succeed Thabo Mbeki as president.

Former South African deputy president Jacob Zuma is suing leading newspapers and radio stations for 63m rand (£4.8m), claiming their coverage of his recent rape trial was defamatory and biased. Most of the 13 lawsuits are against cartoonists and radio DJs who satirised Mr Zuma's statements, such as that he showered to prevent HIV infection. Mr Zuma risks compounding his damaged reputation by pressing the high-profile lawsuits against South Africa's most popular papers and radio stations.

The high-ratings Highveld radio station responded to the charges by repeating its comical song "I am Zuma", for which it is being sued for ridiculing the former deputy president's testimony. Not to be outdone, Mr Zuma's lawyers quickly added the song's second airing to their charges and increased the amount claimed from the station to 7m rand. Award-winning cartoonist Jonathan Shapiro is being sued for 15m rand for three cartoons used by Independent Newspapers, a nationwide company. "I'm not losing any sleep over this," he said at the group's leading newspaper, the Johannesburg Star. "We have freedom of speech in this country, and satirists should not be made to shut up."

Star editor Moegsien Williams said the legal action would not stifle "critical examination of a man who has ambitions to become president of South Africa".

Mr Zuma, 63, was reinstated as deputy president of the ruling party, the African National Congress, after he was found not guilty of raping a 31-year-old HIV-positive woman. He has resumed his campaign to succeed Thabo Mbeki as president but faces a separate corruption trial scheduled to begin on July 31. He could face several years in jail if found guilty of charges that he received bribes from the French arms manufacturer Thint.

Supporters accuse Mr Mbeki's government of pursuing rape and corruption charges to prevent Mr Zuma from becoming South Africa's next president. Government officials say they are merely letting the law take its course.

With acknowledgement to Andrew Meldrum and The Guardian Unlimited.