Three African National Congress (ANC) legislators who have publicly admitted to voting with the opposition in the no-confidence motion against President Jacob Zuma face disciplinary action.
About 35 MPs from the ruling party supported the motion in a secret ballot that sought the removal of President Zuma from office in parliament last week.
The motion was however unsuccessful after it failed to get enough votes.
The ANC secretary-general, Gwede Mantashe, said on Tuesday that the party would punish defectors.
“Three of them have confirmed they voted with the opposition. We will have to deal with that situation because if we don’t we will destroy the essence of being an organisation,” he said.
“We are not going to have lie detectors, but if they come out and say: ‘Yes, I voted with the opposition’, you are no longer following your own conscience, but you are daring your own party,” Mr Mantashe added.
It has since emerged that the decision to discipline the ANC dissenters was taken at a meeting of the party’s national working committee on Monday. A day earlier, President Zuma had called on ANC to identify and punish those who voted against him.