Arouri was assassinated on Tuesday evening in a targeted Israeli drone strike on the Southern Suburb of Beirut.
In a statement afterwards, Iranian Foreign Ministry Spokesperson Nasser Kanaani said the Zionist regime had resorted to the targeted killing after suffering "heavy and irreparable defeat" in the face of Palestinian resistance movements during the al-Aqsa Storm operation.
He said the assassination took place after Gaza's people and resistance groups staged "heroic steadfastness" in the face of a genocidal war that the Israeli regime has been waging against the coastal sliver since the operation, Press TV reported.
Still referring to the assassination, the spokesman said by perpetrating such atrocity, the criminal and fragile Zionist regime proved once again that it was "founded upon assassination and crime."
Arouri's martyrdom, he added, would heighten the impetus for resistance and anti-occupation struggle not only across Palestine but also throughout the region and among the world's freedom-seeking people.
The Iranian spokesman denounced the Israeli regime's violation of Lebanon's sovereignty and territorial integrity during the drone attack.
He insisted that international organizations, especially the United Nations Security Council, had to issue "immediate and effective" reaction to the Zionist regime's acts of terror.
Kanaani finally warned the Israeli regime and its supporters about the consequences of Tel Aviv's new adventurism.