Prime Minister Sanae Takaichi said during her first visit to the White House that Japan condemns Iran's actions during the war, including attacking neighboring Gulf countries and effectively closing the Strait of Hormuz.
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"Iran's development of nuclear weapons must never be allowed," she said, speaking through an interpreter. "That is why we, Japan, have been urging them and also reaching out to other partners in the world."
READ MORE: Trump's failed strong-arming of allies on Iran shows that pressure is losing its effect
Takaichi said she brought a specific proposal to the White House on Thursday to "calm down" the global energy markets.
Trump has implored Japan to help the U.S. reopen the Strait of Hormuz, due in part to its heavy reliance on imported oil.
Trump says he's 'not putting troops anywhere'
Asked about the possibility of deploying U.S. ground troops to Iran, Trump responded, "No. I'm not putting troops anywhere."
He then said he could deploy military forces wherever he wants, and wouldn't tell reporters about his plans.
Trump added, however: "I'm not putting troops."
Trump tries to justify $200 billion Iran war ask
The Pentagon is signaling that it needs an additional $200 billion for the war with Iran, but the president said Thursday that his administration also needs it for other reasons.
"This is a very volatile world," Trump said from the Oval Office. He said the emergency spending, which would need congressional approval, would be a "very small price to pay" to ensure the nation's military stays in top shape.
Trump says he urged Netanyahu 'don't do that' amid fallout from Israeli attack on gas field
Asked if he'd spoken to the Israeli prime minister about the attack, Trump said, "Yeah, I did, I did. I told him, 'Don't do that.'"
Trump continued, "And he won't do that." But he added, "We've — we're independent. We get along great. It's coordinated. But, on occasion, he'll do something. And if I don't like it. And so we're not doing that anymore."
Trump appeared to be suggesting that he'd spoken to Netanyahu only after the attack on Iran's South Pars natural gas field. A person familiar with the matter told The Associated Press that the United States was informed about Israel's plans to strike, but did not take part.
Trump invokes Pearl Harbor in talking about launching the Iran war
The U.S. president was pressed by reporters in the Oval Office to explain why he did not coordinate or inform allies, such as Japan, before launching the war.
"We didn't tell anybody about it because we wanted surprise," said Trump, who then said, turning to Japanese Prime Minister Sanae Takaichi: "Who knows better about surprise than Japan? Why didn't you tell me about Pearl Harbor, OK? Right?"
The Dec. 7, 1941, Japanese bombing of the U.S. Navy base at Pearl Harbor in Hawaii killed more than 2,300 Americans. The U.S. declared war against Japan the next day.
Treasury secretary says U.S. is going after Iranian defectors' money
The U.S. says Iranians who allegedly defected from the government or military and transferred money abroad are facing scrutiny from Washington.
"At Treasury, we've seen where they've wired their money out of the country. We're coming for that. We're going to get it back to the Iranian people," Treasury Secretary Scott Bessent said alongside Trump at an Oval Office meeting Thursday.
Trump added that there have also been "a lot of military defections" in Iran. "I don't blame them for that," he said.