Paralympian Oscar Pistorius will not be released from jail on Friday, as was expected.
Pistorius was given a five-year jail term 10 months ago for the killing of girlfriend Reeva Steenkamp on Valentine's Day in 2013.
He was acquitted of murder and convicted of culpable homicide, an unintentional but still unlawful killing.
He was due to be released this week under house arrest but Justice Minister Michael Masutha has stepped in to halt the release, saying the decision is "premature".
Double-amputee runner Pistorius is currently imprisoned in the Kgosi Mampuru II Prison in central Pretoria - his release was approved in June on the grounds of his good behaviour.
Under South African law, an offender who has been given a prison sentence of five years or less is eligible to move on to correctional supervision after they have served one-sixth of their sentence - in Pistorius' case, 10 months.
In a statement explaining his decision, Mr Masutha said the Parole Board's decision taken in May to release him had no legal basis because Pistorius had not at the time served one-sixth of his sentence.
The statement said: "In the circumstances, the CSPRB (Correctional Supervision and Parole Board) has been requested to review the decision of the Parole Board".
"The consequence of this decision is that the earlier decision of the CSPB to place the offender under correctional supervision is suspended until the Parole Review Board has decided on the matter".
Plans to give early release to the 28-year-old have been criticised by Ms Steenkamp's family, as well as a women's group that has petitioned the justice minister over the matter.
The Progressive Women's Movement of South Africa said the decision to free him was "outrageous" and "an insult" to victims of abuse.
The Supreme Court is set to hear an appeal from prosecutors in November, who are asking judges to overturn the initial verdict and convict Pistorius of murder.
If he were convicted of murder, he would face a minimum sentence of 15 years in prison.
A statement from Ms Steenkamp's parents, reacting to the appeal, said: "We are still struggling with coming to terms with losing our precious daughter Reeva and her loss is felt even more this week as we would have celebrated her 32nd birthday on 19 August."
"As a family we want to continue to honour Reeva's memory and will commemorate her birthday by focusing on the Reeva Rebecca Steenkamp Foundation, celebrating her life, what she stood for and the joy she brought into so many lives."
In a previous letter, Ms Steenkamp's family told the parole board "10 months for taking a life is simply not enough".
