Its national currency has plummeted over the previous year amid an economic crisis. He said that, in parallel, Iran will look more defiant in the public eye, with the potential of the Islamic republic dragging negotiations out for a couple of years.
Iran's military was also quoted as saying it would hold air drills on Monday and Tuesday to prove the country's defensive capabilities.
Since Trump took over at the White House in early 2017, the United States has set Iran in its sights, accusing it of seeking to destabilise the Middle East. "SWIFT is no different than any other entity, and we have advised SWIFT the Treasury will aggressively use its authorities as necessary to continue intense economic pressure on the Iranian regime", said Steven Mnuchin, US Secretary of the Treasury.
The Islamic Revolution Guards Corps commander added, "Our enemies intend to isolate us like an island but today the page has turned and Americans themselves are being gradually isolated, as even their traditional allies" are distancing themselves from the U.S. "That is who really understands the actions we are taking", he added.
Pompeo also remarked on President Donald Trump's "sanctions are coming" message, which he tweeted out in the form of a dramatic Game of Thrones-style poster Friday. We've done all of this, too, Chris, while making sure that American consumers don't suffer. There is no difference. He qualified that transactions for "humanitarian" purposes would be exempt, as they had been in the past, but cautioned that "banks must be very careful that these are not disguised transactions". "They will definitely have a gradual escalating impact on economic conditions and, subsequently, on the relations between Iran and the US". Its rial currency lost more than two-thirds of its value since May and now trades at 145,000 to one USA dollar, down from 40,500 to $1 a year ago. The economic chaos prompted mass anti-government protests at the end of past year that resulted in almost 5,000 reported arrests and at least 25 people being killed. Sporadic demonstrations still continue.
Washington is re-imposing the sanctions after Mr Trump in May pulled out of a 2015 accord aimed at curbing Iran's nuclear ambitions.
Another signatory to the nuclear deal, China, has said it regrets the the re-imposition of sanctions and that its lawful trade with Iran should be respected.
With the sanctions clampdown, Trump is seeking to push Iran to end uranium enrichment outright, and halt its ballistic missile development and support for proxy forces in Yemen, Syria, Lebanon, and elsewhere in the Middle East.
The US stance has already inflicted serious pain on Iranians, with the country's currency, the rial, losing more than two thirds of its value since May.
On Sunday, Mr. Pompeo affirmed the global community's backing of Mr. Trump's efforts against Iran.
Oil prices dipped on Monday as the start to USA sanctions against Iran's fuel exports was softened by waivers that will allow some countries to still import Iranian crude, at least temporarily.
The Trump administration said it has asked these countries including Turkey, Iraq, Italy, Japan and South Korea to bring down their oil purchase to zero as soon as possible.