Israel-Iran updates: Iran launches more missiles at Israel, sirens sound in Tel Aviv and Jerusalem

In remarks before the UN Security Council, Iranian Ambassador Amir Saeid Iravani claimed that 78 people had been killed in Israeli attacks across Iran -- using the term "martyred" -- and that another 320 had been injured.

In his remarks, Iravani also blamed the U.S. for its support of Israel, saying the latest strikes had been carried out "with full intelligence and political support from the United States regime."

The U.S. has said it was not involved militarily.

Iravani also said any country that stands behind Israel now would be viewed as "complicit," and called on the UN Security Council to take decisive action against Israel.

“Supporting Israel today is supporting war crimes, crimes against humanity, and the deliberate undermining of global peace and security,” he said.

Iravani also emphasized that the attacks could have consequences that spread across the region and "endanger millions of lives."

-ABC News' Shannon Kingston

The U.S. was represented at the UN Security Council's emergency session on Friday by State Department Senior Bureau Official McCoy Pitt, who said the U.S. was advised by Israel that the actions carried out against Iran overnight were "necessary for its self-defense."

"Every sovereign nation has the right to defend itself and Israel is no exception,” Pitt said. "The United States was informed of the strikes ahead of time but was not militarily involved in these strikes."

Pitt repeated Secretary of State Marco Rubio’s statement, saying Iran and its proxies should refrain from targeting American interests in the Middle East in response to the attack, and stressed that the Trump administration would continue to pursue diplomacy with Iran.

"The United States will continue to seek a diplomatic resolution that ensures Iran will never acquire a nuclear weapon or pose a threat to stability in the Middle East," he said. "Iran’s leadership would be wise to negotiate at this time."

-ABC News' Shannon Kingston

Calls for restraint from Iran in the face of Israel's attacks were "unjustified," Iranian Foreign Minister Abbas Araghchi said in a statement on his conversation with the U.K. Foreign Secretary David Lammy on Friday.

Iran's response to Israel's attacks "will be firm and decisive," Araghchi also said.

A large portion of Iran's primary enrichment site -- Natanz -- "has been destroyed" in Israeli strikes on the country's nuclear sites, International Atomic Energy Agency Director-General Rafael Grossi told the United Nations Security Council.

Grossi also reported that there was significant damage to the site’s electricity infrastructure and that its backup generators have also been destroyed. He said although there was no indication of a physical attack on underground cascade, the loss of power to it may have resulted in damage to the centrifuges.

The IAEA also said the radioactivity levels surrounding the site were normal, meaning there was no immediate threat to the environment or population.

"However, due to the impacts, there is radiological and chemical contamination inside the facilities at Natanz," Grossi said, calling it "manageable with appropriate radiation protection measures."

"I have repeatedly stated that nuclear facilities must never be attacked regardless of the context or circumstances, as it could harm both people and the environment. Such attacks have serious implications for nuclear security, nuclear safety and safeguards, as well as regional and international peace and security," Grossi said.

-ABC News' Shannon K. Kingston