Mohsen Rabbani is the Iranian consular officer who was serving in Buenos Aires at the time of the AMIA bombing who has been thought to be the mind (and the hand) behind said bombing.
Nisman's investigation always pointed against the supposed cover that Cristina Kirchner gave to Iran during the investigation of the AMIA case.
In this radio interview, Rabbani says everybody just assumed Iran was behind the AMIA bombing, but there is no proof of that, and that he is sure Nisman was murdered (or forced to commit suicide) to avoid him going to court and making a fool of himself.
He also added that Nisman was funded by the US and Israel to pinpoint Iran as the AMIA attacker.
If you have been watching Nisman' series on Netflix and you are unsure whether Iran or the government killed Nisman, according to Rabbani you should look elsewhere (US and Israel). To be honest, the investigation has been very confusing with mixed results and I never thought that Iranian or Argentinian intelligence could set up the murder scene that well...