Khamenei's Advisor issues threat after US attack: ‘Bases used by American forces could be attacked’

The police departments in New York, Washington DC, and Los Angeles issued advisories stating that additional forces have been deployed across the cities.

Iran has issued threats to US bases in the Middle East after air strikes targeted Tehran's nuclear sites on Sunday.

Protesters chant slogans as they hold up posters of the Iranian Supreme Leader Ayatollah Ali Khamenei in a protest following the US attacks.(AP)

Ali Akbar Velayati, an advisor to Iran's supreme leader Ayatollah Ali Khamenei, said that bases used by the American forces could be attacked in retaliation to the US strikes.

"Any country in the region or elsewhere that is used by American forces to strike Iran will be considered a legitimate target for our armed forces," Velayati said according to IRNA news agency.

"America has attacked the heart of the Islamic world and must await irreparable consequences," he added.

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The threat from Iran came after Donald Trump early Sunday announced launching surprise strikes on a key underground uranium enrichment site at Fordow, along with nuclear facilities in Isfahan and Natanz.

Though the US launched the attack on the nuclear facilities using B-2 stealth bombers, bunker-buster bombs and Tomahawk missiles, some officials cautioned that the extent of damage was unclear.

Iranian Supreme Leader Ayatollah Ali Khamenei also vowed punishment for Israel, saying the “Zionist enemy has made a grave mistake.”

Taking to X, the official handle of the Iranian supreme leader vowed to intensify attacks against Israel, but made no mention of the US attacks.

"The punishment continues. The Zionist enemy has made a grave mistake, committed a major crime; it must be punished—and it is being punished. It is being punished right now," Khamenei's post read.

Iranian President Masoud Pezeshkian also vowed that the US would "receive a response" to the attacks, according to news agency AFP.

Ali Shamkhani, another Khamenei advisor, said that "even if nuclear sites are destroyed, game isn't over, enriched materials, indigenous knowledge, political will remain."

Rafael Grossi, director of the International Atomic Energy Agency (IAEA), told an emergency meeting of the UN Security Council that craters were visible at the Fordo facility, but no one had been able to assess the underground damage.

Meanwhile, people gathered in central Tehran on Sunday waving flags and chanting slogans to protest against US and Israeli attacks.

Trump calls for regime change in Iran?

US President Donald Trump urged Iran to end the conflict hours after he announced surprise strikes on three sites- Fordo, Isfahan and Natanz.

"We had a spectacular military success yesterday, taking the 'bomb' right out of their hands (and they would use it if they could!)" Trump said on social media.

Trump also raised the question of a regime change in Iran, calling for 'Making Iran Great Again.'

"It's not politically correct to use the term, 'Regime Change,' Trump posted on his Truth Social platform. "But if the current Iranian Regime is unable to MAKE IRAN GREAT AGAIN, why wouldn't there be a Regime change??? MIGA!!!" Trump said.

In an address to the nation hours after the attack, Trump claimed success for the operation, and Vice President JD Vance followed up Sunday morning.

"We know that we set the Iranian nuclear program back substantially last night," Vance told ABC, adding that Iran still had its highly enriched uranium.

"We're going to work in the coming weeks to ensure that we do something with that fuel," he said. "They no longer have the capacity to turn that stockpile of highly enriched uranium to weapons-grade uranium."

US on high alert

In view of the possible threat from Iran, the US State Department has issued a worldwide caution alert for its citizens travelling or living abroad.

"There is the potential for demonstrations against US citizens and interests abroad," the government statement said. "The Department of State advises US citizens worldwide to exercise increased caution."

Meanwhile, the police departments in New York, Washington DC, and Los Angeles issued advisories saying that additional forces have been deployed to religious, cultural, and diplomatic sites.

The Department of Homeland Security also warned that the "Iran conflict is causing a heightened threat environment in the United States."