IRIS) was an unbuilt Iranian rocket, derived from the Shahab-3 medium-range ballistic missile.
According to Iran it was intended to be a space launch vehicle,[1] after a slip by the Defense Minister in which he acknowledged it as a "more capable ballistic missile than the Shahab-3".
[2] According to Western observers, it was intended to be part of a nuclear-capable ballistic missile.
[4] In 1997, an American satellite captured evidence of a Shahab-4 test facility in Parchin.
[citation needed] In 1999, it was suspected that the Shahab-4 was largely derived from NPO Yuzhnoye's R-12 Dvina, which in its single-stage variant, had a maximum range of 2,000km and a circle of equal probability of 2,400m.