Iran said it will step up efforts to tackle problems created by the US sanctions that are crippling its economy, while a senior Iranian official warned of a "painful response" if it comes under further attack.

Six months after US-Israeli strikes against Iran, the war appears to be at a stalemate. A preliminary ceasefire accord reached in June has unraveled and little progress has been made in diplomatic efforts to get the peace process back on track.

After a pause in military action for much of August, tit-for-tat strikes have resumed with US Central Command saying it hit three Iranian tankers on Saturday after Iran's Islamic Revolutionary Guard Corps launched ballistic missiles at two US Navy ships.

Following the attacks, Iran's Parliament Speaker Mohammad Baqer Qalibaf said that the US should understand that the rules of the game in the war against Iran have changed "before it is too late."

"From now on, any attack against Iran's interests and security will receive a faster, heavier and more painful response," he said in a speech published on his Telegram channel.

Strait of Hormuz

Tehran has shown it retains the capability to attack US interests in neighboring countries and to shut down oil flows through the Strait of Hormuz, through which a fifth of global oil supplies passed prior to the conflict.

However, the US campaign to throttle Iran's economy by blockading its oil exports and stopping sanctions evasion is growing increasingly difficult to withstand, three senior Iranian sources have said.

Qalibaf added that alongside the military front, Iran's main battle was now over production and people's livelihoods.

He cited sharp currency fluctuations, inflation, unemployment and market management as major challenges, adding Iranians could tolerate hardship but not mismanagement or inaction and expected the government to act quickly.

Iran's Economy Minister Ali Madanizadeh said Tehran planned to respond to US economic pressure with reforms and rejected the notion that sanctions would cause it to change course, according to state media.

"They speak of economic pressure and isolation, of breaking off financial ties and they think that by pressuring the economy of a country they can change the decisions of its people," Madanizadeh said.

"I have to clarify one point: the responsibility of reforming Iran's economy is with its government and people, not with the US Treasury."

Separately, Economy Ministry deputy Morteza Zamanian said the ministry's "Economic War Headquarters" was doubling down on its work to resolve problems caused by the war, according to Tasnim news agency.

Iran is the third-largest producer in the Organization of the Petroleum Exporting Countries and exported 90% of its crude via its Kharg Island export hub before the war. Flows have been disrupted since a US blockade of Iranian oil exports began in mid-April.

Kharg island hit 550 times

US Central Command said on X that as of September 6 it had redirected 92 commercial vessels, disabled three and boarded two to ensure strict compliance with its blockade.

Iran's Oil Minister Mohsen Paknejad said the island had been hit around 550 times in previous months but continued to operate.

Iran has also imposed a blockade on the Strait of Hormuz, creating an issue for US President Donald Trump by pushing up fuel prices globally ahead of midterm elections for his Republican Party in November.

However, US Energy Secretary Chris Wright said oil was getting through the waterway.

Tasnim news agency reported that four US missiles hit a tanker in the area of Kharg's anchorage. Tasnim quoted local sources as saying there were no casualties and the tanker's crew was being evacuated.

No American personnel were harmed, Central Command said.

On Sunday, Tasnim reported that the IRGC had shot down a US surveillance balloon over Erbil in northern Iraq, describing it as part of a broader effort to eliminate US aerial surveillance and early-warning systems in the region.

Israeli strikes kill four in Lebanon

Israeli strikes killed four people, including two women, in southern Lebanon, the Lebanese health ministry said, as Israel retaliated for what it said were Hezbollah drone attacks within areas occupied by its troops.

Despite a US-brokered ceasefire with Hezbollah agreed in June, the Israeli military is operating in what it has declared as a security zone in southern Lebanon.

Lebanon's health ministry said that two men were killed in a town on the edge of the zone occupied by Israeli troops, while the two women were killed in Arab Salim, which sits well north of the occupied area. Two girls were among six others injured in that strike.

Lebanese President Joseph Aoun's office called the strikes, which it said destroyed a hospital and damaged a finance ministry building, "a dangerous escalation" that targeted "purely civilian administrations and health centers."

"President Aoun held the Israeli side fully responsible for this ongoing escalation, calling on the United States and the international community to take immediate action to stop these violations and hold the perpetrators accountable," it said.