It has been a year and half since France asked South Africa the authorisation to
interrogate the exiled Rwandan General Kayumba Nyamwasa over his role in the
1994 plane crash in Rwanda.
But RFI's Sonia Rolley has learned that the South African authorities have not even responded to France's request.
French anti-terrorist investigator Marc Trévidic is currently probing the plane crash that took place on the 6 April 1994 in Kigali, Rwanda, in which two French pilots died.
The plane was carrying Habyarimana and is believed to have crashed following an attack on the plane
In March 2012 Trévidic asked the South African authorities for permission to question
Nyamwasa, who was head of intelligence for Kagame's Rwanda Patriotic Front (RPF) at the time.
He is currently the subject of an arrest warrant over his alleged role.
A formal request was sent in June 2012.
But sources close to the case have told RFI that the South African authorities have
yet to reply.
Last July Nyamwasa told RFI he had information about the crash that could implicate Kagamé, adding he was willing to speak to Trévidic.
South African Foreign Affairs ministry spokesperson Clayson Monyela declined to comment, referring RFI to the justice ministry, which did not respond to our calls.
France's justice ministry also refused to comment.
"The South African authorities seem to be embarrassed," said the Habyaramina family's lawyer Philippe Meilhac. "But someone who says openly that he has something to say should be given a hearing."
Trédivic's predecessor on the case, Jean-Louis Bruguière, was criticised in Kigali and Paris when he implicated the RPF in the crime.
Trédivic's investigation is said to have reached no clear conclusion as to whether the missile that downed the plane was fired by hardline Hutu sectarians or the RPF, which was formed by the Tutsi diaspora.
But, although most evidence seems to imply that it was fired from a camp under hardline Hutu control or from nearby, the judge seems ready to consider other hypotheses.