President Trump said the United States would resume bombing Iran if he did not like the preliminary agreement, hours after leaders from the Group of 7 nations called the deal a “breakthrough.”

President Trump said it would be signed on Sunday, but Iran’s Foreign Ministry cautioned that the timeline could be slower.

The exchange came after President Trump said Iranian forces had shot down a U.S. Apache helicopter near the Strait of Hormuz.

An Iranian negotiator returned to Pakistan on Sunday, despite the United States’ abruptly calling off a trip there by its two top negotiators.

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The two American envoys are expected to leave Saturday for Pakistan. Iran’s foreign minister, Abbas Araghchi, arrived in Islamabad on Friday.

With hours to go before President Trump’s 8 p.m. Eastern time deadline for Iran to agree to reopen the Strait of Hormuz or face intense attacks, negotiators feverishly worked toward a deal. Pakistan, an intermediary, proposed a two-week cease-fire.

President Trump moved the deadline to reopen the major transit route for oil tankers from Friday to April 6. Stocks fell sharply and oil prices rose.

Tehran offered its own terms to end the fighting that include a demand for reparations. Israel, concerned that the war might end before it can dismantle Iran’s weapons programs, plans to ramp up its attacks.

Iran maintains publicly that no negotiations are taking place, but Mr. Trump claimed that Iran was so near defeat that it had little choice but to talk. Still, Iranian missiles and drones struck across the region.

Israel’s military said it was targeting infrastructure in the Iranian capital. The head of the International Energy Agency warned that the global energy crisis caused by the war was now worse than the oil shocks of the 1970s.

President Trump said that he would “obliterate” Iran’s electricity plants if it did not open the Strait of Hormuz within 48 hours. Iran dismissed the ultimatum as its missiles hit southern Israel, including near the country’s main nuclear research center.

The concert in Seoul’s historic center was a grand homecoming for a pivotal force of South Korean soft power. RM, the group’s leader, performed through an ankle injury.

The move reversed earlier efforts to impose “maximum pressure” on the country and reflected how little success the Trump administration has achieved in calming global markets.

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The price of oil eased only slightly after the Trump administration sought to calm markets. A drone attack caused fires at a major Kuwaiti oil refinery for a second straight day.

Oil prices had been gyrating this week, after a new round of attacks on major energy facilities in Iran and Qatar raised concerns about energy supplies.

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“I think it’s important that I be here,” President Trump said of asking China to reschedule a summit. Earlier, he disparaged allies for failing to embrace his request for help to reopen the Strait of Hormuz.

Iran has largely closed the Strait of Hormuz to America and its allies. The U.S. energy secretary, Chris Wright, acknowledged energy prices could remain high, even as President Trump has called for other countries to send warships to secure the passage.

After earlier calling for Iranians to rise up, the president on Friday expressed skepticism about a popular uprising against the government. U.S. officials said another 2,500 Marines and as many as three more warships were heading to the Middle East.

After surging about 10 percent on Thursday, oil prices had little reaction to the decision by President Trump to waive sanctions on the sale of some Russian crude.

The U.S.-Israeli war on Iran, now in its 12th day, shows no sign of easing. Three ships were hit by projectiles near the Strait of Hormuz, a conduit for a fifth of the world’s oil.

British officials told Prime Minister Keir Starmer of Peter Mandelson’s close ties to Jeffrey Epstein before Mr. Mandelson was appointed U.S. ambassador.

Lebanese leaders and aid groups warned of a growing humanitarian crisis as Israel targeted Hezbollah. The Pentagon said 140 American service members had been wounded, eight severely, in the war.

President Trump claimed that Iran had surrendered. He made the statement after the country’s president said earlier that Iran would end strikes in Gulf states, with caveats. Qatar and Bahrain reported incoming fire.

Italy pledged air defense weapons to help Gulf nations defend against Iran’s retaliatory attacks. Iranian drones landed in Azerbaijan, a day after NATO shot down a missile headed to Turkish airspace.

The Defense Department released the name of a fifth American killed in an Iranian attack on Sunday, and released the name of another soldier believed to have died in the same incident. The State Department said a charter flight was returning to the U.S. with Americans wanting to leave the region.

The U.S. announced the names of four soldiers who were killed by an Iranian drone on Sunday. The leader of the U.S. Central Command said more than 50,000 troops, 200 fighters, two aircraft carriers and bombers were participating in the fighting.