US President Donald Trump has warned he will target bridges and power plants across Iran next week unless Tehran agrees to restart negotiations.

The remarks came during a Fox News interview broadcast while the nations continued exchanging strikes for a fourth straight day.

Trump had earlier withdrawn a plan for a 20 percent charge on all shipping through the Strait of Hormuz yet moved ahead with renewed port blockades against Iran.

"Next week it gets really bad for them," Trump stated. "We are going to knock out all their power plants. We are going to knock out all their bridges unless they get to the table and negotiate."

In April Trump had already floated strikes on civilian infrastructure such as bridges and power plants in Iran.

UN human rights chief Volker Turk replied then that deliberately striking civilians and their infrastructure amounts to a war crime under international law.

The 1949 Geneva Conventions forbid attacks on facilities vital to civilian survival.

"I will save the energy targets for last, but ultimately we will hit energy targets," Trump added during the Special Report interview with Bret Baier that aired Tuesday night.

He noted that US negotiators had told their Iranian counterparts Tuesday evening they "better make a deal, or you are not going to have anything left."

The heightened language follows Trump replacing his earlier 20 percent toll idea for the Strait of Hormuz with promises of large trade and investment pacts involving Gulf nations.

The shift occurred hours before US forces launched a seven-hour series of strikes on Iran and reinstated the port blockade.

US Central Command said the attacks struck dozens of Iranian military sites near the strait to reduce threats to commercial vessels and crews.

Iran reported at least seven military personnel killed in strikes on a base near the southeastern city of Bampur.

Tehran meanwhile launched missiles and drones toward US positions in Jordan, Kuwait and Bahrain, according to state media.

Kuwait said its air defenses were engaging the drones while Bahrain sounded air raid sirens and urged residents to seek shelter.

The US accused Iran of deliberately striking civilians after seven commercial ships were hit, leaving nearly a dozen crew members killed, missing or wounded.

The United Arab Emirates reported that Iranian cruise missiles struck two of its tankers, killing one Indian crew member and injuring eight others.

Iran's Revolutionary Guard confirmed the tanker strikes, stating the vessels had ignored warnings and tried to pass through mined waters.

Renewed fighting pushed oil prices higher as traffic through the strait nearly halted.

The waterway remains strategically critical, with Iran claiming authority over its management while also able to disrupt global energy supplies.

Trump had declared the US the guardian of the strait and initially proposed the 20 percent fee before shifting to investment deals after calls from Gulf leaders.

In a Truth Social post he wrote that the fee would be replaced by massive trade and investment agreements that would benefit all parties.

He added that the strait remains open to all traffic except Iranian vessels and that oil continues to flow freely.

After meeting Iraq's new prime minister Trump said he disliked fees yet felt it unfair for the US to protect the route alone.

Iran responded that it would retain control of the strait and warned that the blockade had undermined a prior truce agreement.

Officials in Tehran said further pressure would not force a return to talks.

The US had first imposed the naval blockade in April, lifted it in June under a memorandum of understanding, and has now reinstated the measure.

Shipping data shows traffic at a two-month low while benchmark crude prices have climbed sharply.