South African Communist Party (SACP) second deputy secretary general Solly Mapaila slammed President Jacob Zuma for "handing over the independence of our country to the Guptas".
Mapaila was speaking ahead of the party's national imbizo in Boksburg on Friday.
He said Zuma has created a "parallel state", that he runs with the Guptas, and is not accountable to the ANC which the people have elected into power.
"He exercises patronage power as well as political power and having done all of these things, like servicing his personal business networks, he has become an extremely powerful individual," Mapaila said.
"The main thing we want to deal with is to reconnect with the value system of our movement, reconnect with the masses and institutions that have created possibilities in different sectors of society for the ANC's ideas to be the ideas of democracy."
Mapaila said Zuma is currently a "stumbling block" to this goal.
"We are not against the ANC, we are talking about an individual who has hijacked the ANC and is running the ANC through a faction and making its leadership structure irrelevant," Mapaila said.
The SACP imbizo will run until tomorrow for delegates to share their perspectives on what constitutes South Africa's "problem statement" and the way forward.
The imbizo is to be attended by alliance partners and officials from various sectors committed to "solving the root causes of the problems facing the South African society, overcoming both its secondary and primary challenges and developing the national democracy to its full potential."
Also, on Monday, the Congress of South African Trade Unions will convene a 'Special Central Executive Committee' to finalize the preparations for their upcoming Central Committee meeting. At the meeting, the federation will also do an assessment of the May Day celebrations and prepare for a possible Alliance Political Council (APC) meeting.