The head of Mossad said Tuesday the Israeli spy agency will not rest until Iran's oppressive theocratic regime is overthrown and replaced with one that poses less of a threat to the world.

"Our mission is not yet complete," Mossad Director David Barnea said during a Holocaust memorial ceremony at the Israeli Foreign Ministry in Jerusalem. Tuesday was Holocaust Remembrance Day, or Yom HaShoah.

"We did not think that our mission would be completed immediately with the fading of the battles, but rather we planned, and we planned to continue, and this will be manifested even after the time of attacks on Tehran," Barnea said, according to The Jerusalem Post.

Mossad's role in the campaign, he said, will end "only when this radical regime is replaced."

"The regime that wants to destroy us must disappear from the world," he said of Iran's leadership, which has avowed to destroy Israel.

Regime change in Iran, Barnea said, "is our mission. We will not stand by, watching, in the face of another existential threat."

Barnea, whose five-year term ends in June, will be replaced by Military Secretary Maj.-Gen. Roman Gofman. He also responded to critics who argued the operation failed to achieve all its objectives after President Donald Trump declared a two-week ceasefire on April 7.

"We did not think this mission would be completed the moment the fighting subsided," he said, according to Israeli National News. "But we certainly planned for our campaign to continue and to be expressed in the period following the strikes in Tehran. Our commitment will be fulfilled only when this extremist regime is replaced. That regime, which seeks our destruction, must pass from the world."

Barnea also revealed Tuesday that the Mossad operated "in the heart of Tehran" during the campaign against Iran, which began Feb. 28 with U.S. and Israeli forces targeting Iran's political leadership and military infrastructure.

"We brought precise intelligence to the Air Force, and we hit missiles that threatened Israel," he said, according to The Times of Israel.

He also referred to Israel's strategic alliance with the U.S., which he called "the strongest power in the world," noting that historic cooperation during 40 days of fighting helped thwart Iran's central objective, the destruction of the state of Israel.

He concluded his speech with a firm message linking his professional duty to the moral imperative of Holocaust Remembrance Day.

"This is our mission," he said, according to Israeli National News. "We will not stand idly by in the face of another existential threat. With a clear command, never again."

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