Anti apartheid activist Ahmed Kathrada, who died in Johannesburg on Tuesday morning, was sentenced to life imprisonment with Nelson Mandela for fighting injustice imposed by the South Africa's white minority rulers but he will also be remembered for his scathing criticism of the corruption that riddled the ANC-led government.

Mr Kathrada, 87, who was part of a group of eight who was sentenced with Mr Mandela in 1964, was a regular at demonstrations and marches around South Africa, frequently offering his support to students protesting for free tertiary education or workers fighting for higher wages.

It was his criticism of President Jacob Zuma however, that brought him back into the headlines.

In April last year, after South Africa's highest court found that Mr Zuma had violated his oath of office by refusing to abide by an order by the country's corruption ombudsman to return at least some of the public money spent on upgrading his rural home, Kathrada pleaded with the president to resign.

"Now that the court has found that the president failed to uphold‚ defend and respect the Constitution as the supreme law‚ how should I relate to my president?