WASHINGTON/JERUSALEM/ABU DHABI/CAIRO/NICOSIA/LONDON - US President Donald Trump said Sunday that he has agreed to resume nuclear negotiations with Iran's new leadership.

"They want to talk, and I have agreed to talk, so I will be talking to them," Trump was quoted as saying by The Atlantic magazine in a phone interview.

"They should have done it sooner. They should have given what was very practical and easy to do sooner. They waited too long," said Trump. He did not specify whom he would speak with.

Asked whether his conversation with the Iranian side would happen in two days, Trump said, "I can't tell you that."

He said that some of the previous Iranian negotiators were no longer alive.

"Most of those people are gone. Some of the people we were dealing with are gone," he said. "That was a big hit," he added, referring to the joint Israeli-US strikes on Iran starting on Saturday.

On whether he had any indication of renewed Iranian threats against the US homeland since the start of the attack, Trump said, "I don't want to tell you that."

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He also expects that the attack on Iran will not disrupt Republican efforts before mid-term elections in the United States to convince voters that his administration is focused on the US economy, and that the attack's effect on oil markets, which reopen Sunday night, would likely be less disruptive on American pocketbooks than some analysts had predicted.

Trump also said on Sunday afternoon that US combat operations "continue at this time in full force," predicting there would be more US casualties in the coming days.

"Combat operations continue at this time, in full force, and they will continue until all of our objectives are achieved. We have very strong objectives," Trump said in a six-minute video message on Truth Social, without specifying what the objectives are.

"Sadly there will likely be more before it ends," he said of the possibility of more US casualties, saying that "that's the way it is."

3 US soldiers killed

Three US soldiers were killed in action and five others seriously injured as part of the military operation against Iran, the US Central Command said Sunday.

Several others sustained minor shrapnel injuries and concussions, said the command in a statement on social media, adding that they are "in the process of being returned to duty."

"The situation is fluid, so out of respect for the families, we will withhold additional information," the command added.

Trump repeated his call on members of the Iranian Islamic Revolutionary Guard Corps to "lay down their arms" for "full immunity."

Earlier on Sunday, Trump told Fox News that 48 senior Iranian officials have been killed in the strikes on Iran.

He also said on Sunday the US forces have sunk nine Iranian warships and largely destroyed Iran's navy headquarters.

Israeli military chief Eyal Zamir said late Sunday that the joint US-Israeli operation against Iran would continue for "many more days" following an initial strike targeting Iran's top leadership.

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"We are less than 48 hours into the operation, and many more days of combat lie ahead," Zamir said at Kirya military headquarters in Tel Aviv, where he approved plans to extend the offensive.

He described the opening attack as a "surprise" strike of "great force," which killed Iran's Supreme Leader Ali Khamenei and senior military officials.

Araghchi: Iran defending itself

Iranian Foreign Minister Seyed Abbas Araghchi told ABC News on Sunday that no country's leader has the right to tell Iran not to respond to the ongoing US-Israeli massive airstrikes on Iran, saying that his country has every right to defend itself and the Iranian forces "are capable enough to defend our country."

"We are defending ourselves, and we have every right, every legitimate right, to defend ourselves," said Araghchi. "What we are doing is the act of self-defense. There are huge differences between these two," he said.

"We are defending ourselves; whatever it takes; and we see no limit for ourselves to defend our people, to protect our people," he added.

When asked if a negotiated settlement with the United States was still possible, Araghchi suggested that he was doubtful, saying that the US-Iran nuclear talks in recent years had become "a very bitter experience" for Iran.

The United States and Israel began large-scale airstrikes against Iran on Saturday morning, prompting Teheran to retaliate with waves of missile and drone attacks on Israel and US military bases in the Gulf region.

Iran's IRGC says it hit three oil tankers

Iran's IRGC said on Sunday it struck three oil tankers belonging to the United States and Britain in the Gulf and the Strait of Hormuz with missiles, setting the vessels on fire.

In a statement on its official outlet Sepah News, the IRGC said it also targeted US military installations in Kuwait and Bahrain. It said strikes on Ali Al Salem Air Base in Kuwait rendered it completely out of service, destroyed three naval infrastructure structures at the Mohammed Al-Ahmad naval base, and hit a US naval command and backup center in Bahrain.

Another US base in Bahrain was reportedly hit by two ballistic missiles. The IRGC claimed the attacks caused 560 US casualties, though the US has not confirmed the report.

Following the announcement, International Maritime Organization Secretary General Arsenio Dominguez urged shipping companies to exercise "maximum caution" and, where possible, avoid the affected region. He stressed that freedom of navigation is a "fundamental principle of international maritime law."

The IRGC also said it destroyed a US missile defense radar in the United Arab Emirates and struck a US naval vessel in the Indian Ocean, state-affiliated Tasnim news agency reported Monday.

The IRGC said a precision missile destroyed a radar of the Terminal High Altitude Area Defense (THAAD) in Al-Ruwais, Tasnim reported, citing the IRGC.

In a separate strike, a US carrier group refueling ship was hit by drone and missile fire 700 km off Iran's southeastern city of Chabahar, leaving it "non-operational," the report said. US Central Command has not confirmed the Iranian claims.

UAE closes embassy in Teheran

The UAE announced Sunday the closure of its embassy in Teheran, and the withdrawal of its ambassador and all members of its diplomatic mission from Iran.

The UAE's foreign ministry said in a statement that the decision was made in the wake of Iranian missile attacks targeting its territory, which it said have affected civilian areas.

Amid the ongoing military conflict in the region, the UAE's Capital Market Authority said Sunday that stock markets in the country, the Abu Dhabi Securities Exchange and the Dubai Financial Market, will remain closed on Monday and Tuesday, adding that further measures will be taken if necessary.

As airlines in the UAE are adjusting flight schedules in response to regional airspace closures, authorities in Dubai and Abu Dhabi said Sunday that they have directed hotels to extend the stays of guests affected by flight disruptions.

Explosion at British air base in Cyprus

Meanwhile, an explosion was reported late Sunday near the British Royal Air Force Akrotiri based in Limassol in southern Cyprus, according to local media.

A strong blast was heard in the vicinity of the British air base, with sirens activated and aircraft seen taking off from the facility, according to Philenews.

Cyprus Mail reported that around midnight, UK military personnel stationed at the base were instructed to take cover after the explosion was heard.

According to the report, personnel were informed of the situation and advised to return to their residences and remain indoors until further notice.

It remains unclear whether there have been any casualties or the extent of the damage caused.