The South African Communist Party said President Zuma was silent on the terms of reference of the Commission of Inquiry into State Capture.
The President announced on Tuesday night that Deputy Chief Justice, Raymond Zondo, would head up the inquiry.
Opposition parties have said that Zuma had no choice in the matter, with his hand being forced by a court order late last month.
SACP spokesperson, Alex Mashilo, said the Inquiry must not only seek to uncover the conduct of some people but all those who may have rendered our state or parts thereof vulnerable to control by forces other than the public.
"It would be inappropriate for the President to decide the terms of reference for an investigation on allegations he is implicated. The situation reaffirms the correctness of the March 2017 decision of the SACP that it was time for President Zuma to resign in the best interests of the ANC, the Alliance and the people of South Africa as a whole," he said.
Meanwhile, new trade union, African Federation of Trade Unions, welcomed the decision by President Zuma.
Saftu said although the president been left with no legal and political alternative, following the order of a full bench of the North Gauteng High Court this was a victory for all South Africans, especially those trade union, civil society and other activists
Spokesperson, Patrick Craven, however, warned that Commission will not on its own rescue the country from the disaster into which it had been plunged by those who looted state coffers.
"The Commissioners will require many months to investigate all the allegations already in the public domain and much more which are now likely to arise. We cannot sit back and wait for its report before taking other action against those responsible," he said.
Craven said the ANC NEC is expected to discuss the possible recall of the president adding that this move would be supported by the trade union.
Zuma's announcement came on the eve of the ANC's National Executive Committee meeting in East London on Wednesday which is reportedly expected to discuss his future.
