Oscar Pistorius
Oscar Pistorius will not be released from prison this Friday (21 August) Getty Images

South Africa's justice ministry has said that Oscar Pistorius will not be released from jail on Friday (21 August), and the decision to cut short his five-year sentence for manslaughter was taken with "no legal basis."

It declared that the decision to release Pistorius early "was taken prematurely", and have sent the decision back to the parole review board. His release date has been suspended, subject to review.

Pistorius was convicted of manslaughter in 2014 after shooting dead his girlfriend, model Reeva Steenkamp, on Valentine's Day 2013. Paralympic champion Pistorius said he believed that she was an intruder, and shot her dead through a closed bathroom door.

Under South African law Pistorius is eligible for release under "correctional supervision" having served a sixth of his sentence. However women's rights groups in South Africa declared the decision "an insult" to victims of abuse, and Steenkamp's family opposed the early release.

His release would have fallen two days after Steenkamp's birthday, as well as during the Women's Month campaign to highlight violence against women.

Prosecutors have launched an appeal against the manslaughter verdict, arguing that Pistorius knowingly killed Steenkamp and should be punished for murder. South Africa's Supreme Court will hear the appeal in September.

Pistorius's family told Reuters they are "shocked and disappointed" he will not be released on Friday.

After his release from prison, Pistorius would serve the rest of his sentence under house arrest.