The former head of the Rwandan gendarmerie is on trial alongside three of his colleagues for their roles in the 1994 killings.
They are accused of genocide, crimes against humanity and war crimes and have pleaded not guilty. This trial started in September 2004.
Testifying as the first defence witness for General Ndindiliyimana, Colonel Marchal explained in his examination in chief that he had not come to render any service or favour.
The Belgian officer, who was in charge of the Kigali sector, explained that he had found in the person of General Ndindiliyimana an interlocutor "in whom he had all confidence".
He gave an example of how they had set up joint patrols between the Rwandan gendarmerie and the UN forces to maintain peace but the efforts were senselessly wracked following the killing of then Rwandan President Juvenal Habyarimana, which sparked the killings.
The plane carrying President Habyarimana was shot down by unknown assailants near the capital, Kigali on April 6, 1994.
"General Ndindiliyimana was convinced that Rwandans had to participate in the development of their country and should have hope for the future", he claimed.
The cross-examination of Marchal continues Friday.
The prosecution will cross examine the former Rwandan top solider on Monday and Tuesday.
Ndindiliyimana is the second defendant to present his defence case in the joint trial.
© Agence Hirondelle