Former president Jacob Zuma will spend his 80th birthday in hospital on Tuesday.
The Jacob Zuma Foundation said Zuma is currently undergoing tests after falling ill on Sunday.
Spokesperson Jimmy Manyi told eNCA Zuma was supposed to meet with his lawyers on Sunday when he started feeling unwell.
“I’m not a liberty to disclose the exact details of that unwellness. We just thought it’s one of those things that you sleep over and wake up and its all gone. But it looks like the next morning the situation actually deteriorated further,” said Manyi.
“The doctors have looked at the situation and even for them to find certainty they have to run tests. He has to be observed now over a period, I don’t know what period, but that’s how things stand right now.”
This is not the first time Zuma has been admitted to hospital.
In September last year, the former president was granted medical parole during his 15-month sentence for contempt of court at the Estcourt Correctional Centre in KwaZulu-Natal.
The nature of his illness was not specified, but a statement said he would complete the rest of his sentence in the community under special conditions.
Zuma had been in hospital for a month where he had undergone surgery.
Meanwhile, Carl Niehaus, the spokesperson of the disbanded uMkhonto we Sizwe Military Veterans Association and fervent supporter of Zuma, wished the former president a happy birthday.
In his message he spoke of “all the awful things” that had been done to Zuma.
“How our own ANC leaders who are now in government have turned against you, betrayed you, hunted you like an animal. I will stand with you together with so many other comrades. We will never betray you, for us, you are our commander… and shame to your enemies,” he said.
On Monday, Zuma’s corruption trial was postponed yet again to 17 May 2022.
Judge Piet Koen deferred the trial due to Zuma’s reconsideration application before the Supreme Court of Appeal (SCA).