South Africa's Constitutional Court ruled against ex-president Jacob Zuma, 79, Tuesday, citing him for contempt of court prompted by his refusal to answer for corruption charges.
Following his unwillingness to appear before a graft panel, Zuma was sentenced to 15 months in jail.
"The majority judgement orders an unsuspended sentence of imprisonment for a period (of 15 months)," judge Sisi Khampepe said, adding that "the Constitutional Court can do nothing but conclude that Mr Zuma is guilty of the crime of contempt of court."
"I am left with no option but to commit Mr Zuma to imprisonment, with the hope that doing so sends an unequivocal message... the rule of law and the administration of justice prevails."
The judge ordered the former South African president to hand himself over within five days.
Zuma, 79, stands accused of enabling the looting of state coffers during his nearly nine-year stay in office.
What is the background to the Jacob Zuma case?
In 2018, Zuma was forced to step down after being forced out by his own party, the ruling African National Congress (ANC), following a series of corruption scandals.
Under immense pressure, Zuma set up the inquiry shortly before he was ousted. In July 2019, he testified only once before walking out of court and accusing the chair of the commission, Deputy Chief Justice Raymond Zondo, of being biased against him.
Since then, Zuma has repeatedly ignored requests to appear in court, citing medical issues and time needed to prepare for a different corruption trial.
In November, he appeared in court briefly but left before he could be questioned. Zondo turned to the Constitutional Court and requested it intervene.
Zuma then refused to participate in contempt of court hearings, addressing an angry letter to Chief Justice Mogoeng Mogoeng that described an "atmosphere of judicial hostility" and "humiliation."