Iran's Foreign Minister Abbas Araghchi Makes First China Trip Since War, Meets Wang

"I hope the Chinese tell him what he needs to be told, and that is that what you are doing in the straits is causing you to be globally isolated," Secretary of State Marco Rubio said at a White House press briefing on Tuesday. "It is in China's interest that Iran stopped closing the straits. It's harming China as well."

The US Treasury has sanctioned Chinese private oil refiners for processing Iranian crude, including Hengli Petrochemical (Dalian) Refinery Co., one of the country's largest. China responded by ordering companies to defy US sanctions in an unprecedented step that raised tensions before the Trump-Xi summit.

The Chinese president has called for the strait to be reopened, but Beijing has so far turned a cold shoulder to Washington's request to help it unblock the waterway. Next week's summit offers the two leaders the first opportunity to discuss the Iran war in person.

Trump on Tuesday sought to downplay tensions with China over the conflict, saying Xi has "been very nice" about it.

"He's been very respectful. We haven't been challenged by China," he told reporters at the White House. Trump has previously suggested that Beijing may be providing help to Tehran, claiming the US had intercepted a boat with a "gift" from China bound for Iran.

The key question is what role Beijing is willing to play to end the conflict that's roiled global markets and supply chains - and what kind of pressure it's prepared to put on Tehran. China has portrayed itself as a stabilizing force and neutral mediator in the war, while seeking to balance strategic ties with Iran and its vast economic interests in the Gulf.

Last month, Iranian officials credited a last-minute push by China with securing their acceptance of a ceasefire brokered by Pakistan - though Beijing hasn't publicly taken credit for it. Chinese state media have also pushed back on those claims, saying China's role in the ceasefire is overstated.

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Still, Araghchi's visit highlights China's status as one of the few geopolitical heavyweights with some leverage over both Iran and the US.

Before his trip to Beijing, Araghchi visited Russia, Iran's other major backer, meeting President Vladimir Putin in Moscow on April 27. Putin will likely travel to China in May, according to a Russian business daily, Vedomosti, for what would be his first trip abroad this year.

Beijing has maintained close conacts with Moscow during the Iran war.

Russian Foreign Minister Sergey Lavrov was the first counterpart Wang called to discuss the conflict, on the day after the initial strikes began in late February. The two diplomats also held extensive talks in Beijing during Lavrov's visit last month.