The war entered its fourth week on Saturday.
President Donald Trump announced "major combat operations" against Iran on Feb. 28, with massive joint U.S.-Israel strikes attack targeting military and government sites, officials said.
Ayatollah Ali Khamenei was among those killed in Tehran on the first day of strikes and his son Mojtaba Khamenei was chosen to succeed him. Iran is responding with missile and drone attacks targeting Israel, regional U.S. bases and multiple Gulf nations. Iran is also attempting to block some shipping traffic through the Strait of Hormuz.
Israel is also intensifying its long-running strike campaign against the Iran-backed Hezbollah militia in Lebanon.
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Asked about Israel potentially pursuing objectives that diverge from U.S. interests in Iran, Secretary of Defense Pete Hegseth said the U.S. "holds the cards."
"The United States military controls the fate of that country," he said. "Iran has the ability to make the right choices. It should not going, forward target, Arab allies, Arab countries."
Asked about reports that the Pentagon sought an additional $200 billion from the White House in supplemental funding for the war, Secretary Pete Hegseth indicated that the figure could "move."
"As far as $200 billion I think that number could move," he said. "Obviously it takes money to kill bad guys. So we're going back to Congress and our folks there to ensure that we're properly funded."
Secretary of Defense Pete Hegseth said Iran's goal for decades has been targeting Americans around the world, saying the regime, has been a "threat" to American "across every theater."
"They have been at war with us, whether we acknowledge it or not, for 47 years," Hegseth said.
"What President [Donald] Trump would not tolerate is a regime of that nature being closer and closer to nuclear capabilities, a capability they would have said they would want to use," Hegseth said.
Asked how close the U.S. is to achieving President Donald Trump's objectives in Iran, Secretary of Defense Pete Hegseth declined on Thursday to set a timeline.
"We wouldn't want to set a definitive time frame on that, but as we've said, we're on plan," Hegseth said.
"You hear a lot of noise about widening or new missions, or speculation about what we should or should not be doing. This is a clear set of objectives. The president has given us every capability we need to accomplish that. We've got the best in the world in uniform, executing it on the ground," Hegseth said.
Hegseth said the end of the war "will be at the president's choosing."
