President Donald Trump threatened to escalate U.S. air strikes in Iran on Tuesday, as he declined to rule out a potential "ground campaign."

Speaking on Fox News just hours after the U.S. began its naval blockade against Iran, Trump said he'd consider it because "sometimes you need a ground campaign," although he added that "we have other people that will do the ground campaign for us."

The United States launched its fourth day of air strikes on Wednesday, and Trump warned he planned to continue the escalation until Tehran returns to the negotiating table.

"We're going to hit them very hard tonight," he said. "We're going to hit them very hard tomorrow night. We're going to hit them very hard the night after. And then next week it gets really bad for them because next week comes the power plants. Next week comes the bridges. We're going to knock out all that power plants. We're going to knock out all their bridges unless they get to the table and negotiate."

However, when asked if the war with Iran had fully resumed, Trump sidestepped the question, telling Fox News' Trey Yingst that the journalist could "define it any way you want."

"Certainly we're beating them up really badly," he added.

Retired U.S. Vice Admiral Robert Murrett told Newsweek on Tuesday that he believes the conflict between the United States and Iran has "entered a new phase."

"This is certainly an inflection point that has transpired over the last three or four days," he said.

The U.S. military’s Central Command announced on Tuesday it had begun launching new strikes against Iran as of 3 p.m. ET. An hour later, the U.S. began its naval blockade against Iranian ports.

Central Command said that the strikes would "continue degrading Iranian capabilities used to attack commercial shipping in the Strait of Hormuz."

Treasury Secretary Scott Bessent also announced Tuesday that the U.S. had frozen more than $130 million in assets connected to the Central Bank of Iran.

"The U.S. Treasury is committed to disrupting and degrading Iran’s illicit financial activities, including its abuse of digital assets," he said in a statement. "Today, Treasury’s Office of Foreign Assets Control sanctioned multiple wallets tied to the Central Bank of Iran, resulting in the freeze of over $130 million. We will continue to aggressively follow the money and deny the Iranian regime access to the proceeds of its illicit revenue schemes."

Why Did The Strikes Start Again?

Earlier Tuesday, Trump said that he tried to reach a deal with Iranian leaders over the weekend, but that they pulled out.

"I gave them a chance. I wanted to give them a chance at making a deal. You know, we had a deal two days when it was done, and then all of a sudden, they couldn't do it. They didn't like something about the deal," he explained.

"They shot first. And that was a big mistake that they shot first because we have been knocking the hell out of them," the president continued.

As the Strait of Hormuz has once again become a dangerous flashpoint, these Iranian sites could be the focus for an escalation of further attacks.

Explosions were reported in the southern Iranian port city of Bandar Abbas on Tuesday, and in turn Iran has threatened to retaliate against American military sites across the region, putting at risk Bahrain, Jordan, Kuwait and Oman.

Iran's Islamic Revolutionary Guard Corps (IRGC) said Tuesday it had targeted Bahrain, Jordan and three tankers that had traveled through the strait, which is the transit point for one-fifth of the world's oil and gas.

"They've (Iran) been very careful in terms of which countries they have selected," said Murrett. "The subtext of that is that they're willing to attack facilities where they don't think they can inflict casualties on the United States, in which they understand there's a red line," he said, "but the IRGC doesn't seem to think that's something that's going to constrain them."

Two of the ships, Mombasa and Al Bahiyah, were linked to the United Arab Emirates and were set ablaze, killing one mariner and wounding eight others, according to the UAE defense ministry, which has threatened retaliation. Newsweek has contacted the UAE defense ministry and the Pentagon for comment.

Bahrain's Ministry of Interior sent three separate alerts for residents to seek shelter after the IRGC said it targeted weapons depots, a satellite communications center, a building that housed U.S. forces, and a U.S. Navy air traffic control radar.

Jordan said it had intercepted four missiles from Iran.

Major General Saud Abdulaziz Al-Otaibi, the official spokesperson for the Kuwaiti Ministry of Defense, said that it had also intercepted dozens of drones, five cruise missiles and a ballistic missile since yesterday.

"Additionally, one of the naval vessels belonging to the Kuwaiti Naval Force was targeted, resulting in injuries to four members of the Armed Forces, who received the necessary medical care and treatment; their condition is stable," he continued in a statement shared on X.

"The Armed Forces affirm their continued execution of their missions and duties with efficiency, within the framework of ongoing readiness and constant preparedness, thereby enhancing the security of the homeland and preserving the safety of citizens and residents."

The actions have ended the memorandum of understanding (MOU) of June 17, intended by Tehran and Washington to reopen the Strait of Hormuz, which Iran has closed and the U.S. has blocked.

About 180 Iranian lawmakers have called on Tehran to treat the MOU as terminated and to continue pursuing retaliation for the killing of former Supreme Leader Ali Khamenei and other senior Iranian officials.

The group also called for a special committee to review negotiations with the United States and oversee implementation of conditions set by Supreme Leader Mojtaba Khamenei. The lawmakers also voiced support for the armed forces and Iran's exercise of sovereignty over the Strait of Hormuz.

Trump Reverses Course on Strait Tolls

Trump said in a social media post Monday that he would require a 20 percent reimbursement for countries traversing the Strait, before reversing course Tuesday. He explained that he received feedback from leaders that upfront investments into the U.S. would be more beneficial than enacting a tax.

"I thought it was good. I was called by different people, different countries, kings, Emirs...and they said we'd love to do it a different way," he explained, saying they told him: "'We'd love to invest in the United States with billions and billions of dollars... we would like to invest tremendously in the United States as opposed to charging a fee.'"

"I like that actually because I don't think anybody should be able to charge a fee for the Strait or for any other Strait relationship in terms of other sections of the world," Trump continued, adding, "I don't think anybody should be really in that position, but we were doing it as a reimbursement. The Gulf states are going to invest a tremendous amount of money into the United States, and that was very satisfactory to me. I think it's actually much better."

In his post on Truth Social on Monday, he vowed to reinstate his blockade of Iranian ports before saying on Tuesday that he would create a full blockade only for Iranian ships.

"Oil is flowing like never before, thanks to the awesome Power of the United States Military," Trump said in a post to Truth Social on Tuesday. "Because of them, and all members of the Most Powerful Military anywhere in the World, BY FAR, the Strait of Hormuz is open to ALL Ship traffic except for Iran — and that is because of their lying, violent, malicious leadership, which is taking them down the path of TOTAL DESTRUCTION."

"We will therefore have a FULL Blockade, but only on Ships coming to and from Iranian ports, or carrying anything have [that has] to do with Iranian cargo," he said, adding, "Based on highly productive conversations with Middle East leadership, I have decided to replace the 20% United States Reimbursement Fee with Trade and Investment Deals that the various Gulf States will be making into the United States.

"Those Investments will be MASSIVE but, at the same time, extraordinarily good for them, and their future," he continued.

**Saudi-Yemen Fighting Threatens to Pull Houthis Into War**

Meanwhile, the threat of Iranian-backed Houthis being dragged into the war was raised when Saudi Arabia said the militant group fired ballistic missiles and drones at a civilian airport in the kingdom’s southwestern city of Abha.

The attacks were the first major fighting since a 2022 truce that ended a seven-year conflict between northern Yemen’s Tehran-aligned rulers and several Arab countries.

The militant group had accused the Saudis of bombing its airport in the capital Sanaa to prevent the landing of a plane returning the Houthi delegation from the funeral of Iran’s slain leader, Ali Khamenei.

Murrett, who is deputy director of the Institute for Security Policy and Law at Syracuse University, said that Saudi Arabia has "done a pretty good job of limiting the number of tensions that they have with Iran. Compared to all the other Gulf states, they have not had nearly as many attacks."

But regarding the attack on Sanaa, "they may have said that this might be a good time to settle some scores that they continue to have with Yemen."

**Trump’s Threats To Bridges and Desalination Plants**

The U.S. has said it had targeted, destroyed or degraded Iranian military infrastructure, especially around the Strait of Hormuz, rather than civilian infrastructure with reported strikes on Bandar Abbas, Qeshm Island, Sirik, Bushehr province and the Jask/Hengam Island area.

US Central Command said its latest strikes have targeted Iranian air defense systems, command and control networks, coastal radar sites and anti-ship missile capabilities.

Radar installations used to track shipping and military activity in and around the Strait of Hormuz have also been targeted by the U.S. with the aim of degrading Tehran’s ability to hamper shipping in the critical waterway.

Meanwhile, last week at the NATO summit in Ankara, Trump reiterated a threat he had made in March that the U.S. could target desalination plants if the conflict continued to escalate. He also said that the U.S. could capture Kharg Island, Iran’s main oil export site, raising the specter of a marked U.S. escalation.

"The electric plants where they make their electricity — we will, if we have to, take them out," Trump said, "I don’t want to do that." Regarding desalination plants, he added, "we’ll take them out if we have to."

Destroying infrastructure needed by civilians violates Article 54 of Additional Protocol I to the Geneva Conventions, which lists "drinking water installations and supplies" as off-limits.

Legal experts warned that targeting desalination plants would be against international law as they are generally considered civilian objects, unless they only supply water to a military base.

Contact Newsweek editors on this story: Francis Mao, Trevor Davies and Gray R. Thomas