A panel of three high court judges, headed by the Lord Chief Justice Lord Thomas, ruled that there were outstanding legal issues the court had to decide, the British Press Association reported.
Dewani is fighting removal to South Africa to face trial over his wife Anni’s death until he has recovered from mental health problems, said to include depression and post-traumatic stress disorder.
His lawyers have stressed at various hearings that he will be willing to defend himself at trial once he is fit to do so.
Thomas ruled his case must be reopened to consider two key issues. The first related to Dewani’s status as “an accused person”. The second concerned whether it would be “unjust and oppressive” to extradite Dewani “regardless of the prognosis” of his mental condition.
Anni Dewani’s mother Nilam Hindocha said outside court: “I am the mother of a murdered daughter. How long do I have to wait?
“It is nearly three years since she was killed and we have kept our dignity and respect throughout. I was brought up to believe British justice is the best in the world so it is very hard to understand why we are still here.”
In July, Chief Magistrate Howard Riddle ruled at the Westminster Magistrate’s Court that Dewani should be extradited and rejected his attempt to stay in the UK for further hospital treatment.
He said Dewani, from Bristol, was still not fit to plead or stand trial at present, but there was evidence he would receive the care he needed in South Africa.
Judge Riddle had originally given the go-ahead to Dewani’s extradition in 2011, but had to reconsider the position after the high court allowed his appeal in March last year.
Dewani is suspected of ordering the killing of his new wife Anni, 28, who was shot as the couple travelled in a taxi on the outskirts of Cape Town in November 2010.
So far three men have been convicted for Anni Dewani’s death. Last year, South African Xolile Mngeni was convicted of premeditated murder for shooting her.
Prosecutors claimed he was a hitman hired by Dewani to kill his wife, something Dewani has consistently denied.
Taxi driver Zola Tongo was jailed for 18 years after he admitted his part in the killing. Another accomplice, Mziwamadoda Qwabe, also pleaded guilty to murder and was handed a 25-year prison sentence.
Dewani’s family have said that he remains committed to returning to South Africa “when his health would permit a full trial and when appropriate protections are in place for his health and safety”.