"We are all very grateful and happy," his lawyer Wynanda Coetzee said.

"He should have been allowed to go home a while ago already. His situation is very serious and he is very ill."

Correctional Services Minister Sibusiso Ndebele announced in Pretoria that Selebi would be released from prison on Friday.

An 11-member medical parole advisory board met on June 20 and recommended the release of six offenders, including Selebi, who needed dialysis for kidney failure.

Selebi's wife was a qualified nurse, but it was not clear if she would look after him or if the family would hire professional help.

"There are a lot of financial implications and considerations to take [into account] before they can decide," Coetzee said.

She was not sure if Selebi would be allowed to go home on Friday.

"It came very suddenly, so I don't think it will happen today."

Selebi was president of Interpol at the time of the investigation into claims that he received money from convicted drug trafficker and police informer Glenn Agliotti.

He was convicted of corruption on July 2, 2010, and handed a 15-year jail sentence.

Selebi appealed against the corruption conviction in the Supreme Court of Appeal. In December 2011 he collapsed at home in Waterkloof, Pretoria, while watching the appeal judgment on television. His appeal was denied.

This meant he had to begin his 15-year jail sentence for corruption. It was decided he would stay in Pretoria Central Prison's medical wing indefinitely.

At the time he had not instructed his medical team to apply for medical parole. Selebi had also been trained to administer his own treatment.

He suffers from diabetes and kidney disease.