The UDM wants the "mother of inquiries" into state capture and corruption to begin.
"South Africa is facing the real and present danger of political, economic, social and administrative collapse from unbridled corruption and state capture," UDM leader Bantu Holomisa said in a statement released on Wednesday.
"President Jacob Zuma consistently appeals every court judgment where he is involved... the nation might even give him a new nickname!
"He even seeks to appeal against the decision by Judge [President] Dunstan Mlambo that Chief Justice Mogoeng Mogoeng chooses the judge to head up the commission of inquiry into state capture. Why?"
Holomisa referred to the decision of a full Bench of the High Court in Pretoria, led by Gauteng Judge President Dunstan Mlambo, to dismiss Zuma's application against former Public Protector Thuli Madonsela's report on state capture.
The report recommended that a judge appointed by the chief justice must oversee the judicial inquiry since Zuma is implicated in the allegations of state capture through the Gupta family.
Two days after the conclusion of the ANC's elective conference last month, where it was resolved that the inquiry into state capture must be instituted as a matter of urgency, Zuma lodged his appeal, saying the full Bench had erred.
"What is going on behind the curtains of the president's continuous counteractions in the various courts? Why this dogged reaction and, we hear in this case, accusing the court of erring in law 16 times? Why not just lance the boil and get it over and done with?" Holomisa continued.
Threatening 'political bigwigs'
He added that, if the inquiry goes ahead unhindered and there is a forensic auditing component, it might be "that some folks are fearing where the breadcrumbs might lead".
"The next question could therefore be: 'Is there, maybe, a deal in the wind between President Zuma and his party - or at least some individuals in the African National Congress (ANC), or maybe even a few cabinet ministers?' Which leads to these inescapable questions: Who (really) is being protected by whom, and why?"
He said, not only does the inquiry potentially threaten "political bigwigs", but one wonders which big businesses and/ or business people might also have to come clean.
According to Holomisa, even just a wisp of truth in the allegations could be the ANC's death knell just before the 2019 elections.
He called on South Africans to unite against corruption and state capture.
"Let us exert pressure from every corner to have this inquiry take place long before 2019; the nation requires the truth about the people who they've elected into power.
"If these leaders are innocent, they can stand proudly after being tested in the inquiry... but, if they are guilty, they must go to jail."