The ANC wishes former minister Ronnie Kasrils luck if he is campaigning for spoilt votes, the Sunday Independent reports.

"We are out here campaigning for people to vote for the ANC," secretary general Gwede Mantashe was quoted as saying.

"If he is campaigning for the spoiling of votes, all I can do is wish him luck."

Kasrils and former deputy health minister Nozizwe Madlala-Routledge have reportedly asked South Africans to take a stand against fraud and corruption by spoiling their votes.

The two are garnering support for the "Sidikiwe Vukani! Vote No" campaign, due to be launched at Wits University on Tuesday, the newspaper reported.

The aim of the campaign was to get struggle activists and others not to vote for the African National Congress, or at least spoil their vote, on May 7.

Former home affairs director general Mavuso Msimang said he was not part of the campaign and would not do what those involved were doing.

"Whatever deficiencies that exist within the ANC should be fixed," Msimang was quoted as saying.

He has been critical of the ruling party and recently wrote that "there is a crisis within the ANC".

Executive director of Ahmed Kathrada's foundation, Neeshan Balton, said the ANC veteran was not part of the campaign. Former ANC treasurer general Mathews Phosa said the campaign made a weak case.