Cape Town - ANC stalwarts calling for President Jacob Zuma to step down are bitter former position holders who have declared themselves leaders of the people, the Ex-Political Prisoners' Association (Eppa) has said.In an interview with News24, Eppa deputy national secretary Mpho Masemola said if those who have chosen “a suspicious path” want to challenge the ANC, they should form a political party and take them on through democratic processes. In a statement at the weekend, the association hit out at former political prisoner and former member of Parliament Ahmed Kathrada.The association was equally scathing toward Cheryl Carolus and Trevor Manuel, whom Masemola called “very bitter so-and-so's”.Last week Carolus, who is the ruling party's former deputy secretary general, said, "I call on my president to step down"."I was deeply saddened and thought... this has happened on our watch and all of us need to wake up and fix this on our watch or history has every right to judge us. I never thought I would stand up in public and say how deeply sad I am about what happens in my Parliament."In an interview with Soweto TV last week, Manuel said the country was in a moment of "deep crisis" and it would be in the best interests of South Africa for Zuma to step down. Manual is a former finance minister."The violation of the key oath of office of the head of state ... is a deep crisis. I think it's in all of our interests that the president actually steps aside," he said.'So-called concerned citizens'Masemola challenged the stalwarts to start their own political parties and stand against the ANC at the polls.“We believe in a constitutional democracy. Let us see and witness if the masses will vote for them. We don’t know who they represent. They don’t have a constituency.”Referring to them as “so-called concerned citizens”, Masemola said people should not follow “these kind of leaders”.“What made them concerned now? They belonged to [former president] Thabo Mbeki’s government. They have bitterness. They cannot fool us and people of SA by declaring themselves self-appointed leaders of the people.”The calls for Zuma to step down came in the wake of the Constitutional Court ruling that found that Zuma and Parliament flouted the Constitution by ignoring the Public Protector's findings on Nkandla. It also found that Zuma must pay for the upgrades.