"As the Imam Khomeini said, if each Muslim throws a bucket of water on Israel, Israel will be erased," Mottaki told a conference in Tehran, recalling a saying by Iran's late revolutionary leader Ayatollah Ruhollah Khomeini.
President Mahmoud Ahmadinejad has sparked international outrage for his repeated attacks against Israel, which he has predicted is doomed to disappear and described as a "stinking corpse" and a "dead rat".
His most notorious attack was in 2005 when he repeated another saying from Khomeini calling for Israel to be "wiped from the map".
'Nuclear program entirely peaceful'
Mottaki added: "More than ever, the Zionist regime is disintegrating from within. Today, the Islamic resistance in this region has shattered the regime's legend of invincibility."
While Ahmadinejad and top military commanders regularly predict the demise of Israel, such virulent attacks from the foreign ministry are relatively unusual.
Iran vehemently denies charges of anti-Semitism, pointing to the continued existence in the country of the largest Jewish community in the Middle East outside Israel and saying it is only against Zionism.
Tensions between Iran and Israel have also intensified in the past year over the Iranian nuclear drive.
Israel, the Middle East's sole if undeclared atomic arms power, accuses Iran of seeking a nuclear weapon and, along with its chief ally the United States, has never explicitly ruled out a military attack against the Islamic republic.
But Iran, which does not recognize Israel, insists that its nuclear program is entirely peaceful and aimed solely at generating energy for a growing population.