The African National Congress' (ANC's) own alliance partner, the South African Communist Party (SACP), has called into question former president Jacob Zuma's testimony this week at the Zondo commission into State capture.

SACP spokesperson Alex Mashilo said there might be serious legal implications for Zuma's testimony over spy allegations within the ANC.

"Regarding the old era allegations that former President Zuma made as he vividly, apparently, remembered what allegedly happened that long time ago [compared to what happened very recently which by and large he said he cannot remember or recall], he has the legal duty to furnish evidence.

"In addition, like every person who becomes aware of wrongdoing, he also has the legal duty to report the wrongdoing. To the extent that he has not done so then there may be serious legal implications for him," Mashilo told News24.

Zuma's shocking claims on Monday that some high-ranking Umkhonto we Sizwe (MK) veterans were part of the apartheid intelligence spy network in the ANC during the struggle, have opened up a Pandora's box for the party.

In his testimony, Zuma mentioned Umkhonto we Sizwe Military Veterans Association (MKMVA) council leader Siphiwe Nyanda and former combatant Ngoako Ramatlhodi as alleged apartheid spies.

The former president said he believed the commission was established to bury him and further tarnish his reputation.

The SACP has poked holes in his statement, saying it was Zuma who brought his own reputation under serious question when he said he had appointed people whom he had long known were "spies" collaborating with or working for the apartheid regime into Cabinet.

"At the commission, he came across as contradictory when he alleged, despite having set its wider terms of reference, that it was established allegedly solely to follow and victimise him. It is important to avoid being distracted from the real purpose of the commission.

"It is unbelievable, for example, that Ramatlhodi was a spy. This comrade worked with former ANC president OR Tambo, directly in his office, and was appointed, first as a premier, and then by Zuma himself deputy minister and twice a minister in different portfolios."

Divisions within the ANC and its alliance seem to be deepening as a result of Zuma's testimony.

On Wednesday, the MKMVA hit back at its own council, saying it was a "renegade and factional grouping without any legitimacy or legal standing".

This after the council released a statement in support of Nyanda after Zuma's claims.

On Thursday, the SACP and Ahmed Kathrada Foundation will hold a media briefing with the sole agenda of responding to claims made by the former president at the commission.