South African prosecutors have asked the nation's highest court to reject a bid by Oscar Pistorius's lawyers to appeal against the double-amputee runner's murder conviction.
Prosecutors have filed papers with the Constitutional Court arguing that Pistorius's appeal is not valid, said National Prosecuting Authority spokesman Luvuyo Mfaku.
Lawyers for Pistorius, who killed girlfriend Reeva Steenkamp in his home in 2013, had appealed to South Africa's highest court, saying another court erred when it overturned a manslaughter conviction and declared the Olympic athlete guilty of murder.
Pistorius is under house arrest while the Constitutional Court decides if it will hear the case.
Sentencing on the murder conviction is scheduled for April 18.
Pistorius's legal team maintains that the Supreme Court of Appeal, which convicted Pistorius of murder, ignored his vulnerability as a person with a disability.
It believes the court wrongly rejected a lower court's judgment that Pistorius acted out of fear when he opened fire at what he thought, by his account, was an intruder behind the closed door of a toilet cubicle.
However, prosecutors argue that they had appealed against the earlier manslaughter conviction because of an error in the way the law was applied, rather than any facts of the case, Mr Mfaku said.
Prosecutors in South Africa can appeal against convictions on questions of law, and the appeals court that convicted Pistorius of murder found that the judge who imposed the earlier manslaughter conviction committed a legal error by incorrectly applying a legal principle called "dolus eventualis".
Under that concept, a person can be convicted of murder if he or she foresaw the possibility of someone dying through their actions and went ahead anyway.
The appeals court said that regardless of who Pistorius said he thought was behind the door, he should have known someone could be killed if he fired.