Habyarimana died in the plane shoot-out by unknown assailants near the capital, Kigali. He was returning from a regional peace meeting in Dar es Salaam, Tanzania. Also killed in the plane was Burundi's President, Cyprien Ntaryamira.
Ten Belgian peacekeepers and as many Belgian civilians were killed in the hours that followed because of rumours implying that Belgium was involved in the firing of the missiles which brought down the presidential aircraft.
The Security Council had ordered an investigation into the attack which never materialized, the envoy said in his testimony for the defence of Jerome Bicamumpaka, then Rwanda's Foreign Minister, who is jointly charged with three other ministers in the case known as "Government II" for genocide and crimes against humanity in 1994. The ministers are: Casimir Bizimungu (Health), Prosper Mugiraneza (Civil Service) and Justin Mugenzi (Commerce) All have pleaded not guilty.
"It will always astonish me that we did not succeed in carrying out a serious investigation leading to results", stressed the diplomat.
"I will be the last to affirm what may have happened. We must have intellectual, moral and political honesty to admit that many things have not been answered yet", he added.
The diplomat however said that he did not know Bicamumpaka except for a meeting that he had with him in company of two other ministers after his nomination. He also mentioned the discomfort which he had felt at the time of the formation of the interim government.
The only investigation was carried out by a French judge, Jean Louis Bruguiere, which led to the indictment of nine acquaintances of Rwandan President Paul Kagame.
It is still not over, the prosecution having still not made a decision, which would have then made it possible for the judges to render an order for trial or have the charges dropped.
After the disclosure of the investigation in November 2006, Kigali, which has always accused France of having supported the "government of the genocide", severed diplomatic ties with Paris.
© Hirondelle News Agency