WASHINGTON/TEHERAN/JERUSALEM - US President Donald Trump said Sunday that if Iran does not reach a deal over its nuclear program, "we'll find out" whether Iran's supreme leader was correct in predicting that a US attack on the country would spark a regional war.

Iran's Supreme Leader Ayatollah Ali Khamenei earlier warned that any attack on his country would spark a regional conflict, as the United States continues to build up its forces nearby.

Commenting on Khamenei's remarks, Trump said the United States has deployed what he described as the world's "biggest, most powerful" naval forces to the region and expressed hope that negotiations would lead to an agreement. "Hopefully we'll make a deal," he said.

"We don't make a deal, then we'll find out whether or not he was right," Trump added.

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Trump said Iran began negotiations with the United States on Saturday.

US Ambassador to NATO Matt Whitaker said the same day that Trump has made clear demands of Iran, with the next steps depending on decisions by Iran's leadership. He added that Trump "won't wait forever" for those demands to be met. "The president has been very clear on Iran."

In an interview with CNN on Sunday, Iranian Foreign Minister Seyed Abbas Araghchi said that a "just, fair, and equitable" nuclear agreement with the United States remains achievable in the short term, provided Washington abandons its policy of coercion.

Iran's top security official Ali Larijani had previously said a framework for negotiations was progressing.

Tensions have remained high amid increased US military activity in the region. Trump has sent a "massive armada" to Iran. Meanwhile, a US guided-missile destroyer recently made a port call in Eilat, an Israeli port city at the northern tip of the Red Sea.

Israeli security chiefs meet to assess readiness

Also on Sunday, Israeli Defense Minister Israel Katz held a meeting with military chief Eyal Zamir to assess the military's "operational readiness" following the latter's urgent defense talks in Washington.

The discussions focused on the military's "operational readiness for any possible scenario" amid escalating regional tensions, the Defense Ministry said in a statement.

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The meeting comes after Zamir concluded a weekend visit to the United States, where he discussed coordination of defense strategies with US Chairman of the Joint Chiefs of Staff Dan Caine and senior Pentagon officials. The talks reportedly centered on preparing for potential US military action against Iran.

Qatari PM visits Teheran 

Qatari Prime Minister and Foreign Minister Sheikh Mohammed bin Abdulrahman bin Jassim Al-Thani visited Iran on Saturday to discuss regional peace and stability, Iranian Foreign Ministry spokesman Esmaeil Baghaei said Sunday.

Iranian Foreign Minister Araghchi and Larijani met with the Qatari minister, Baghaei told reporters in a press conference.

The meetings were "in continuation of the good offices offered by and consultations among the region's countries regarding regional developments, and aimed at exchanging views on protecting peace and stability in the region," Baghaei said.

The top Qatari diplomat reiterated his country's "support for all efforts aimed at reducing tensions and achieving peaceful solutions that enhance security and stability in the region," Qatar's Foreign Ministry said in a statement.

"He also stressed the need for concerted efforts to spare the peoples of the region the consequences of escalation and to continue coordination with brotherly and friendly countries to address differences through diplomatic means," it added.

Iran parliament considers European armies as 'terrorist groups'

Meanwhile, Iran's Parliament Speaker Mohammad Bagher Ghalibaf said on Sunday his country considers European Union militaries "terrorist groups."

He made the remarks in response to the EU's designation of the Islamic Revolutionary Guards Corps as a terror organization on Thursday, according to the ICANA news agency, which is affiliated with Iran's legislative body.

"The consequences of this action will be borne by the EU," Ghalibaf said. He described the EU's move as "irresponsible," stressing that it was made in compliance with the orders from Trump and Israeli leaders.

Iran releases list of nearly 3,000 killed in recent unrest

The office of Iran's President Masoud Pezeshkian on Sunday also released a list naming 2,986 people killed during recent unrest in the country.

In a statement posted on its website, the president's office said the list, which includes both civilians and security personnel, was compiled from data provided by the Iranian Legal Medicine Organization at Pezeshkian's order.

The office said the total death toll stands at 3,117, meaning 131 victims remain unidentified. It pledged to release a supplementary list once their identities are established.

The statement emphasized a commitment to transparency and accountability, noting that all victims were children of Iran and pledging that no bereaved family would be left unheard.