PRETORIA, South Africa - Oscar Pistorius will try to appeal his murder conviction in South Africa's highest court, his lawyer said Tuesday, possibly extending a legal battle that began nearly three years ago when the double-amputee Olympian shot girlfriend Reeva Steenkamp to death in his home.

As Pistorius sat in the dock in a wood-paneled courtroom, defense lawyer Barry Roux unveiled the plan to take the sensational murder case to an 11-judge court known for abolishing the death penalty and affirming basic human rights after the 1994 end of white minority rule in South Africa.

If the Constitutional Court chooses not to hear the case, Pistorius will be back in a lower court on April 18 for the start of a sentencing process, meaning he will remain under house arrest under bail terms announced Tuesday for at least the next several months.

Pistorius had already been living under restrictions at his uncle's home in Pretoria since October after serving one year of a five-year prison sentence for manslaughter. That conviction, however, was thrown out last week when an appeals court convicted the former track star of murdering Steenkamp, a model who was in a toilet cubicle when her boyfriend fired through the door on Valentine's Day 2013.

Prosecutors said he killed her after an argument; Pistorius said he killed her by mistake, thinking there was an intruder in the house.

On Tuesday, Pistorius was granted bail in the equivalent of $692 in South African currency - he paid an amount 100 times higher when he first appeared in court for the shooting, though he was not placed under house arrest at that time.

Judge Aubrey Ledwaba also instructed that Pistorius be placed under electronic monitoring and restricted the hours during which he may leave his uncle's home.

Bail is often denied in cases where a conviction is overturned for a harsher verdict, but Pistorius' compliance with previous bail and house arrest conditions may have influenced the judge's decision, said Manny Witz, a South African legal expert.