There has been some back-and-forth within the administration on whether they'd offer waivers to countries.
On 7 August, Washington will reimpose sanctions on Iran's purchase of U.S. dollars, its trade in gold and precious metals and its dealings with metals, coal and industrial-related software.
The 2015 landmark nuclear deal provided Tehran with some relief from sanctions in return for curbs on its nuclear program.
Why did Mr Trump abandon the nuclear deal?
Heavier US sanctions, aimed at Iran's oil sector, are due in November.
Iran's currency, the rial, has tanked, losing about half its value against the dollar.
The protests have often begun with slogans against the high cost of living and alleged financial corruption but quickly turned into anti-government rallies.
Last month, the IRGC said it was ready to act after President Hassan Rouhani said that if Washington pressed ahead with its goal of bringing Iranian oil exports down to zero, no oil would pass through the Straight of Hormuz.
Rouhani implied that if the United States signed up again to the nuclear deal and lifted sanctions, then that could pave the ground for negotiations.
"We are always ready to negotiate", Rouhani said on Iranian state television. "But talks need honesty", Rouhani said.
Earlier, Iranian president's chief of staff Mahmoud Vaezi revealed that during Rouhani's last visit to NY for the UN General Assembly session, Trump asked the Iranian delegation eight times to have a meeting with the president. "We'll find out whether they are or not".
The move, which follows through on Trump's May 8 vow to unilaterally withdraw from the multinational nuclear agreement, cheered Israeli Prime Minister Benjamin Netanyahu and members of the president's party, who had long railed against the deal.
At the stroke of midnight on Tuesday, the USA will sanction Iran's central bank, sending a clear message to its European allies: Do business with the U.S., or do it with Iran, but not both.
Pompeo said it would require "enormous change" by Iran to get out from under renewed USA sanctions.
Two countries that have welcomed increased pressure on Iran are its key regional rivals, Israel and Saudi Arabia.
FILE PHOTO: A man walks past an anti-U.S. mural in Tehran, Iran October 13, 2017.
Trump says the U.S.is urging all nations "to make clear that the Iranian regime faces a choice: either change its threatening, destabilizing behavior and reintegrate with the global economy, or continue down a path of economic isolation". On Sunday the judiciary said it had arrested a further seven people, including a former deputy central bank governor and five foreign exchange dealers.
At the same time, a blocking statute - last used to protect European Union firms from United States sanctions against Cuba - will be brought into force in an attempt to insulate firms and keep alive a deal created to limit the Iranian government's nuclear aspirations.
The Trump administration in recent weeks has ramped up a pressure campaign against the Iranian government, decrying its leaders as exploitative and corrupt while supporting protesters on the ground.
"Individuals or entities that fail to wind down activities with Iran risk severe consequences", Trump said.
"That's the behavioral change that we're looking for from the Iranian regime", Secretary of State Mike Pompeo told Metro TV in Jakarta.
"We are determined to protect European economic operators engaged in legitimate business with Iran, in accordance with EU law and with United Nations security council resolution 2231".
While Iran's economy is in poor shape, it isn't in the critical condition it was when the Iran nuclear deal was reached.
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