JOHANNESBURG: A South African high court on Friday tossed out a last-ditch legal bid by former president Jacob Zuma to avoid jail for refusing to appear before graft investigators, reports AFP.

The ruling marks the latest judgement in a long-running drama to go against Zuma, although it does not change his situation as he has already started serving his sentence.

He had been facing a deadline of midnight Wednesday to turn himself in or else face arrest -- a threat that he challenged at the High Court in Pietermaritzburg.

The bid was turned down by Judge Bhekisisa Mnguni, who heard the argument by Zuma's lawyers on Monday.

"I am not persuaded that Mr Zuma has made out a case for this court to grant the relief sought," he said.

He also said his court was not empowered to interfere in decisions made by the Constitutional Court, the country's paramount judicial body.

"What... this application seeks to achieve is to entangle this court in judicial adventurism," he said, adding Zuma's concerns about his health were "not supported by any evidence."

"Unsurprisingly... the rest of Mr Zuma's case then collapses like a deck of cards," he said.

Zuma has separately pleaded with the Constitutional Court to rescind its jail order against him.

That plea will be heard in Johannesburg on Monday.