Mziwamadoda Qwabe pleaded guilty to murder, kidnapping, robbery, and illegal possession of a firearm, prosecutor Eric Ntbazalila told AFP.
In his plea bargain Qwabe stated that he had been recruited by fellow suspect Zola Tongo to take part in a “job in which a husband wanted his wife killed”.
The couple were on honeymoon in Cape Town in November 2010, when she was killed in a murder that prosecutors say was set up to look like a botched carjacking in a vehicle driven by Tongo.
“The agreement was that Zola and the husband would be unharmed and that the deceased would be kidnapped, robbed and killed,” said the statement.
It was meant to “appear like a random criminal act”.
Qwabe stated that Shrien Dewani was let out of the car before his wife was robbed of her possessions and shot dead with a single bullet.
He said his third co-accused Xolile Mngeni, who has a malignant brain tumour which has so far prevented him from standing trial, was the one who fired the shot.
The businessman from Bristol, west of London, had claimed that he was forced out of the car window during the hijacking.
Prosecutors hailed the plea agreement as a step toward firming up the case against Dewani.
“It’s a positive step for the prosecution because we are now a step closer to getting information on what happened on that day, which will shed some light on the role played by Shrien Dewani,” Ntabazalila said.
Dewani returned to Britain with his wife’s body days after the killing, but was later arrested and South Africa is awaiting his extradition to stand trial in Cape Town.
Britain has approved his extradition but on March 30 the London High Court temporarily halted the process, citing mental health grounds.
His lawyers said he was suffering from severe post-traumatic stress disorder and severe depression and argued the 32-year-old’s life could be at risk if he were extradited.
He has strongly denied arranging the contract killing of his 28-year-old Swedish-born wife.
Qwabe said he was “willing and prepared to testify in any subsequent criminal prosecution instituted in regard to this conspiracy”.