VOA Persian's Katherine Ahn contributed to this story
U.S. President Donald Trump imposed what he described as "hard-hitting" new financial sanctions on Iran Monday, specifically targeting the country's supreme leader, Ayatollah Ali Khamenei.
Trump signed an executive order he said would curb access Khamenei and Iran have to world financial markets. Treasury Secretary Steven Mnuchin said the action would "literally" lock up "tens and tens of billions of dollars" of Iranian assets.
Trump called his order a "strong and proportionate" American response to Tehran's shootdown last week of an unmanned U.S. drone. Washington says it occurred in international airspace near the Strait of Hormuz. Iran claims it was over its own airspace.
With just minutes to spare late Thursday, Trump decided not to launch a military response to the shootdown after he learned that 150 Iranians would be killed by a U.S. attack. In announcing the new sanctions, Trump said, "I think a lot of restraint has been shown by us, but that doesn't mean we're going to show it in the future. But we'll give it a chance."
"I think this signals continued resolve by the U.S., if that was in question, after the president refrained from a military response (to Iran's attack on the U.S. drone)," said James Phillips, a senior researcher at the conservative Washington-based Heritage Foundation, in a VOA Persian interview on Monday.
"This is a non-military signal that the administration is sending to show that it continues to be 100% committed to its 'maximum pressure' campaign (against Tehran).. But I think it's more likely to be symbolic than to have genuine substantive repercussions," Phillips said.
In a briefing with reporters on Monday, Mnuchin defended the Trump administration's "maximum pressure" campaign of escalating sanctions against Iran over the past year. He said the sanctions have been "highly effective in locking up the Iranian economy. We follow the money, and it's highly effective."
Trump launched the sanctions campaign in May 2018, when he pulled out of a 2015 international agreement between six world powers and Tehran. Under the 2015 pact, world powers offered Tehran sanctions relief in return for its agreement to restrain its nuclear program.
Trump said he imposed the latest sanctions because of a series of "belligerent acts" carried out by Iran, which U.S. officials say include Iran's targeting of Norwegian and Japanese ships in the Strait of Hormuz with mines days before the attack on the drone.
The executive order is aimed at pushing Tehran back to one-on-one talks with the U.S. over its nuclear weapons program, a year after Trump pulled out of the 2015 six-nation nuclear deal with Iran.
"We'd love to be able to negotiate a deal," Trump said. "Never can Iran have a nuclear weapon. They sponsor terrorism like no one's seen before. I look forward to the day when sanctions can be lifted and Iran can be a peace-loving nation. The people of Iran are great people."
But Senate Minority Leader, Democrat Chuck Schumer, said it is unclear what strategy, if any, the new sanctions fit into.
Schumer said he does not believe Trump is eager to go to war with Iran, but said, "His strategy seems erratic, changing from day to day and week to week. ... I am very concerned that he could bumble us into war."
Iranian Foreign Secretary Mohammad Javad Zarif is among those targeted by the new U.S. sanctions.
He tweeted Monday that Trump is "100% right that the U.S. military has no business in the Persian Gulf. Removal of its forces is fully in line with the interests of US and the world."
Zarif said it is Trump's "B team" - an apparent reference to hawkish National Security Advisor John Bolton and others - that "despise diplomacy and thirst for war."
The Iranian foreign minister was referring to a Trump tweet earlier Monday in which the U.S. leader called on other world powers to do more to secure oil shipments in the Persian Gulf.
Secretary of State Mike Pompeo said Sunday "the world should know that we will continue to make sure it's understood that this effort that we've engaged in to deny Iran the resources to foment terror, to build out their nuclear weapon system, to build out their missile program, we are going to deny them the resources they need to do that."
Iran has defended its missile work as legal and necessary for its defense. Tehran has sought support from the remaining signatories to the 2015 agreement - Britain, China, France, Germany and Russia - to provide economic relief since the U.S. tightened sanctions in an attempt to cut off Iranian oil shipments.