TEHERAN/JERUSALEM -- Iranian Supreme Leader Ali Khamenei said on Sunday that if the United States starts a war against Iran, it will be regional.

He made the remarks at a meeting in Teheran as tensions remain high between Teheran and Washington following the latter's military buildup in the West Asia region, reported the semi-official Fars news agency.

Khamenei said that Iran would not start a war and does not seek to attack any country, "but Iranian people will deliver a hard punch to those seeking to attack and harass them."

"The American should know that if a war is launched, this time, it will be a regional war," he emphasized.

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US President Donald Trump said Sunday that if Teheran fails to strike a nuclear deal with Washington, "we will find out" whether Iranian Supreme Leader Ali Khamenei was right to warn that a US attack could ignite a regional war.

Iran parliament considers European armies as 'terrorist groups'

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 US President Donald Trump and Israeli leaders.

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 Seyed Abbas Araghchi and Secretary of the Supreme National Security Council of Iran Ali Larijani met with the Qatari minister, Baghaei told reporters in a press conference.

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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.

On Saturday night, Larijani said in a post on social media platform X that "the formation of a structure for negotiations (with the United States) is progressing," but did not provide further details.

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Israeli security chiefs meet with Iran

Israeli Defense Minister Israel Katz held a meeting with military chief Eyal Zamir on Sunday 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.

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.