London (CNN) -- A British man accused of orchestrating his wife's murder by hit men while they were honeymooning in South Africa has lost a High Court appeal to block his extradition there until he is fit to stand trial.
The judges ruled that Shrien Dewani can be extradited as long as the South African government pledges to return him to the United Kingdom should he ultimately prove unfit to be tried.
Dewani's lawyers had argued that he should not be extradited while he was unfit to stand trial. He is being treated for post traumatic stress disorder and a depressive illness.
His legal team can appeal the decision at the Supreme Court.
Dewani is accused of hiring a crew of hit men to kill his wife, Anni Dewani, 28, during a taxi ride in Cape Town in November 2010, just over two weeks after their wedding.
Taxi driver Zola Tongo confessed within weeks of the bride's death that he had hired two men to kill her.
In a plea deal with South African authorities, he said he was paid by Shrien Dewani to carry out the hit and to make it look like the two were the victims of a carjacking as they were driving through a township on the edge of Cape Town. Tongo was subsequently sentenced to 18 years in prison for his part in the killing.
In their ruling, the judges at the High Court in London said there was some prospect that Dewani could recover sufficiently to be fit to stand trial.
It is also possible that the continued uncertainty over his extradition could act to deter his recovery.
They also said they were confident in the ability of South Africa's authorities to treat Dewani fairly.
"The death of the appellant's wife Anni occurred over three years ago," they said in their conclusions.
"The interests of justice, including the interests of her family who like other families of murdered persons wish to see a trial take place as soon as is practicable, require expedition and that there should be no further delay, provided that proper protection is afforded to the appellant in the manner we have set out."
CNN's Claudia Rebaza contributed to this report.