The SACP will not close ranks around partners in the alliance movement when things are going wrong, the party's general secretary Blade Nzimande said on Monday.
"Let's tell the truth to ourselves, even if the truth coincides with what the enemy is saying. Let us tell the truth," Nzimande quoted from a speech ANC president Oliver Reginald Tambo delivered in 1984.
Nzimande was addressing workers at Cosatu's central committee meeting in Irene.
He focused on the progress made since President Jacob Zuma assumed power in 2009, the second more radical phase of the national democratic revolution, and solidifying the relationship between Cosatu and the SACP.
He warned of trends which had emerged within the alliance as the ANC approached its 54th national elective congress in December.
A "parasitic patronage faction" was getting active support from the highest echelons of both the ANC and the state.
He defended his party's criticism of the Gupta family, which had been accused of acting like a parallel state. He said the SACP had spoken out when there were threats to "capture" parts of the movement in the past.
Nzimande said the current ructions in the movement were worse than the ones that preceded former president Thabo Mbeki's defeat to Zuma at the ANC's elective conference in Polokwane in 2007.
On the same day, EFF leader Julius Malema warned about the safety of SACP deputy general secretary Solly Mapaila. Malema claimed Zuma was worried about him and that the party should make sure he was protected at all times - but not by the VIP protection unit or the SAPS.
The SACP claimed a gunman tried to kill Mapaila at former SACP leader Chris Hani's memorial recently.
Nzimande said there was an attempt to emulate a Putin-style, authoritarian, low-intensity democracy.
Many ANC members were threatened at the party's national executive committee meeting over the weekend, where a second motion of no confidence in Zuma failed.
"Our comrades, some of them are threatening us in the meetings, saying that they didn't train for nothing as MKs," Nzimande said in Zulu. He was referring to members of the ANC's former armed wing, Umkhonto we Sizwe.
He said progress had been made during the "Zuma years" including in the health sector and the fight against HIV/Aids.
"Nobody will tell us not to talk about the ANC. It's our movement," Nzimande said.
When the problem of factionalism in the 105-year-old movement was raised at the NEC meeting, those who did so were criticised and accused of advancing regime change and sounding like the DA, he said.
"We need to assist the ANC. The ANC is in deep trouble. There is internal stalemate in the national executive committee. These comrades can't provide leadership to themselves and the alliance as a whole."
He said the time to complain was over.
"There is a strong feeling that contesting elections together as allies, but leaving key decisions in the hands of the ANC alone, is no longer acceptable," he said.
On Tuesday, Cosatu's candidate to take over ANC presidency, Cyril Ramaphosa, is expected to address unions.