South African opposition protesters marched on Tuesday to Johannesburg's Constitutional Court, where judges heard a case over public money spent on President Jacob Zuma's private house.
The upgrades at Zuma's homestead, which were valued in 2014 at about 216 million rand (then $24 million), have become a symbol of alleged corruption and greed within the African National Congress (ANC) government.
Among the supposed security work was a swimming pool described as a fire-fighting facility, a chicken run, a cattle enclosure, an amphitheatre and a visitors' centre.
Several hundred protesters from the radical Economic Freedom Fighters (EFF) opposition party marched through the city to the court, chanting "Pay back the money" and "Zuma must fall".
Public Protector Thuli Madonsela, the country's ombudswoman, ruled in 2014 that Zuma and his family had "benefited unduly" from the work on Nkandla property.
In a U-turn ahead of the court hearing, Zuma last week agreed pay back some of the funds, in an apparent attempt to end the two-year scandal.
Despite Zuma's new stance, the two main opposition parties — the Democratic Alliance and the EFF — declined to drop their Constitutional Court bid.
The Democratic Alliance said in a statement on Tuesday that the case's outcome was "crucial to the successful functioning of our constitutional democracy."
All parties are jostling for advantage ahead of municipal elections due later this year that could see a fall in support for the ANC, which has ruled since the end of apartheid.
The president, who has often been accused of allowing corruption to flourish since he came to power in 2009, is under pressure over South Africa's sharply slowing economy.
He will make his annual state of the nation address in parliament on Thursday.
The occasion descended into chaos last year when EFF lawmakers scuffled with security after interrupting him to protest over the Nkandla scandal.
Zuma had previously said he did not order the property upgrades, while an enquiry by the police minister concluded that the work was all security-related.
