Iran’s supreme leader on Thursday warned Israel and the United States that any attack on the country’s controversial nuclear program would be met with an “iron fist.”

In a speech at a military academy in Tehran, Ayatollah Ali Khamenei said, “Anyone who intends to attack the Islamic Republic of Iran is living in a dream and should prepare themselves for strong slaps in the face and the iron fists of the army, Guard Corps and Basijis — in a word, the great Iranian nation.” He referred to the Islamic Revolutionary Guard Corps and members of a paramilitary force affiliated with it, the Basij.

His reaction came two days after the International Atomic Energy Agency released a report that said Iran has conducted secret experiments “relevant to the development of a nuclear device.”

Iran denies the allegations and says the evidence used by the U.N. nuclear watchdog was fabricated by the United States and its allies. It has insisted that its nuclear program is aimed only at generating electricity and ensuring an independent fuel supply for its nuclear power plants.

Khamenei urged all Iranians to continue “with the path of national honor and international power,” signaling that Iran will not compromise in pursuing its nuclear program.

Israeli leaders have reportedly discussed plans to attack Iran’s nuclear sites, while the Obama administration wants to intensify already harsh economic sanctions. Russia, the builder of Iran’s only nuclear power plant, spoke out Wednesday against putting more pressure on Iran. China, the leading buyer of Iranian oil, has cautioned against increasing tensions in the Middle East.

Following Israel’s warnings, dozens of Iranian politicians and commanders have vowed that any attack would be met by strong retaliation.

“If smoke columns rise from our nuclear facilities, then this scenario could happen in other areas,” said Brig. Gen. Massoud Jazayeri, deputy chief of staff of the Iranian armed forces. “The Dimona station in Israel is the easiest target for our military capabilities,” he told Iranian state television’s Arabic language channel, al-Alam, on Wednesday, referring to a secret nuclear plant in the Negev Desert. He added that if Israel committed such a “folly,” it would mean its “disappearance from existence.”

Iran has missiles that can strike Israel, which is believed to possess at least dozens of nuclear warheads. In the past, Iran has also threatened to close off the Strait of Hormuz, a narrow waterway through which oil tankers from the Persian Gulf must pass.

Khamenei, Iran’s supreme leader, stressed that Iran is not planning to attack any nation. But he warned that “aggression, or even threats, will be returned in such a way that the assailants will be imploded from within.”

Such an implosion, a popular theme among Iranian politicians, is on the horizon anyway, Khamenei asserted, adding that Iran enemies are being “internally eaten by worms.” Iran has applauded the Occupy Wall Street protests, claiming that they mark the start of a revolution that will ultimately lead to the fall of the U.S. political system.