Iran and the United States exchanged intensified fire on Thursday in a week-long escalation that has all but torn up last month's truce, but Iran's release of a U.S. citizen was seen as signalling ​a path to avert the resumption of all-out war.

For the first time since a memorandum of understanding paused fighting last month, the United States launched two big waves of air strikes ‌in one day on Wednesday, mostly on targets near the coast in southern Iran.

Iran responded with missiles and drones fired at U.S. military bases in neighbouring countries, including a major barrage at a recently expanded air base in Jordan.

The week of increasingly intense fire has tested the limits of escalation that both sides set during four months of fighting before last month's truce. But in the midst of the attacks, U.S. President Donald Trump hailed the release of a U.S. citizen in Iran as a "gesture of goodwill".

Human rights lawyer Jared Genser identified ​her as Dena Karari, who he said had been "trapped in Iran since December 2024 on bogus charges" and was "now safe and traveling back to the United States". There was no comment from Iran on the ​case.

Over decades of confrontation, the release of U.S. citizens held in Iran has been managed through behind-the-scenes contacts that persisted when formal diplomacy was cut off.

SHIPPING HALTED AGAIN

The ⁠re-escalation has once again nearly halted traffic through the Strait of Hormuz, the world's most important shipping route for oil and gas, sending global energy prices shooting higher. But prices are still well below wartime peaks, suggesting traders ​anticipate the crisis could abate.

Iran triggered the renewed fighting last week by striking ships using a corridor in the strait outside its control, including a drone attack that caused a dangerous fire on board a Qatari tanker filled with liquefied natural ​gas.

Iranian sources have told Reuters that Iran's aim was to establish its authority over the strait. But having made that point, Tehran is not keen for a wider escalation that would torpedo the June memorandum of understanding, which it still regards as giving it most of what it sought.

Trump has declared the ceasefire under the memorandum "over".

Within Iran, the renewed bombing has left residents anxious, following huge week-long memorial events for slain Supreme Leader Ayatollah Ali Khamenei that the authorities depicted as a demonstration of victory and national solidarity.

"Living with ​this fear that war could start again is very exhausting. You cannot live like this. We are tired of war. What is our sin that we have to live this way? Personally, I want diplomacy to prevail," Mahlegha, ​46, a government employee, told Reuters by phone message from Tehran.

IRAN SAYS U.S. STRIKES CAN'T BREAK ITS GRIP ON STRAIT

Iran wants all ships using the Strait of Hormuz to travel only through a channel close to its shores, and has made no secret ‌that it ⁠intends to charge fees for passage at the end of a 60-day negotiation period set in last month's memorandum.

Washington has encouraged ships to use an alternative route to the south, along the Omani coast, without coordinating with Iran.

Since last week's flare-up, Iran has declared the strait closed. The United States responded by reimposing its own blockade of Iran's ports from Wednesday, including firing at an empty tanker in the strait it said was bound for Iran. The U.S. military said it fired Hellfire missiles into the tanker's smokestack near Iran's Kharg Island after it ignored warnings.

U.S. forces say their airstrikes have hit Iranian military targets along the coast to cripple its ability to control the strait. But Iran, which can ​hit ships with missiles and drones from afar, says its ​grip does not rely on such coastal bases.

"The ⁠Americans thought that by attacking some of our bases on the southern coasts of the country, they could take control of this strategic strait," military spokesman Brigadier General Mohammad Akraminia said on Thursday.

Iran can "exert control over the Strait of Hormuz from every single point of its territory," he added.

Three U.S. officials told Reuters that the U.S. strikes could also ​serve as "shaping operations", giving Trump more options by targeting Iranian military capabilities that the U.S. would want to have destroyed before taking bigger steps. "This is helping set the ​stage, if needed," one of the ⁠officials said.

Trump has not ruled out the possibility of using ground forces, including to seize Kharg Island, site of Iran's main oil export terminal. He has repeated threats to hit Iranian power plants and bridges next week unless Tehran resumes negotiations.

Akraminia said that if Trump carried out that threat, Iran's armed forces would strike "all remaining infrastructure" across the region, and the response would be more severe, wider in scope and more destructive than previous attacks.

For now, Iran's retaliatory strikes have been focused on ⁠U.S. bases in ​neighbouring countries. Iran said on Thursday it had targeted U.S. bases in Kuwait and Jordan, including an air base in Jordan that Washington ​has upgraded in recent years into a regional headquarters.

It said the Jordanian base had been used to launch attacks on Iran, including one that struck a target in the city of Ahvaz, causing damage to a nearby children's cancer hospital that had to be evacuated.

"Our neighbours should ​know that providing a base to the Americans and allowing them to fire on Iranian soil is unacceptable and will not go unanswered," Iran's army said.