All South Africans want to hear during President Jacob Zuma's State of the Nation Address is "I am retiring", non-governmental organisation Accountability Now said on Wednesday.
Zuma's credibility was at an all-time low, its director Paul Hoffman told reporters in Cape Town.
However, Zuma would neither resign nor retire on his own as he was too compromised and too protected.
"But the interests of the country would be served if he resigned," he said.
Hoffman said the main problem was lack of confidence in the president as a result of "Nenegate" and the "flip-flop on Nkandla".
Zuma axed Finance Minister Nhlanhla Nene in December, replacing him with relatively unknown ANC member and former Merafong mayor David van Rooyen.
Following public outrage and the rand falling to new lows against the dollar, Zuma replaced Van Rooyen with Pravin Gordhan.
Hoffman said the country, and some in the ruling party, did not trust Zuma anymore, especially following arguments about Nkandla in the Constitutional Court on Tuesday.
The EFF and DA wanted the court to outline the public protector's powers, after Zuma failed to comply with Thuli Madonsela's recommendations that he had to repay a portion of the R246 million spent on so-called security upgrades at his private homestead in Nkandla. They further wanted the court to instruct Zuma to comply with her recommendations.
Hoffman said that during Tuesday's submissions, Zuma "sold senior Cabinet members and parliamentarians down the Nile".
He said it was possible that the Constitutional Court would rule in favour of the opposition parties. The public protector's powers could not be second-guessed.
He said Zuma had been in breach of the Constitution since Madonsela released her Nkandla report in March 2014, as he was obliged to support the public protector's office.
Should the opposition win its Constitutional Court case, they might then use it as a basis for another impeachment vote again. They would not succeed however, as the ANC would use its majority in the National Assembly to defeat the vote, he said.
To redeem his legacy, Zuma should announce during his speech on Thursday that a social economic Convention for a Democratic South Africa would be convened urgently, Hoffman said.
He should also advocate for the creation of an Integrity Commission.