(CNN) The United States officially reimposed all penalties that had been lifted as part of the Iranian nuclear deal as the Trump administration added nearly 700 targets, including 50 Iranian financial institutions, to a sanctions list Monday.

Trump administration officials said the reinstated sanctions marked an intensifying effort to strangle Iran's economy to pressure the regime to change its ways. Any company or country that does business with Tehran will feel the sting of US penalties, they said.

The campaign, a central foreign policy goal for President Donald Trump, marks a gamble as it divides the US from traditional allies in Europe, casts uncertainty into oil markets, is likely to deepen humanitarian suffering inside Iran and, critics say, potentially undercut moderates in Tehran who might be open to working with the US.

'Laser focus'

"We are making it abundantly clear to the Iranian regime that they will face mounting financial isolation until they fundamentally change their destabilizing behavior," Treasury Secretary Steven Mnuchin said Monday in Washington, adding the regime must its stop ballistic missiles program and abandon its nuclear ambitions if wants to seek a path to sanctions relief.

The deal, one of the President Barack Obama's signature foreign policy achievements, has been vilified by Trump since his early campaign days.

"We are watching the Iranian regime with laser focus," Mnuchin told reporters. "If they try to evade our sanctions, we will take action to disrupt their activity time and time again. The maximum pressure exerted by the United States is only going to mount from here."

In a sweeping list, the Treasury Department labeled an additional 700 entities, including individuals, banks, vessels, aircraft and Iran's energy sector as part of its decision to reapply harsh sanctions that kicked in early Monday morning. The reinstated sanctions follow the Trump administration's decision in May to pull out of the international nuclear deal that is still supported by all other parties, including the EU, France, Germany, the UK, Russia and China.

The EU, UK, France and Germany said on Friday said they "deeply regret" the US move. China on Monday said it "regrets" the US decision, adding that the global community "generally opposes the practice of unilateral sanctions and long arm jurisdiction."

Secretary of State Mike Pompeo said that eight countries would get waivers that would allow them to continue importing Iranian oil: China, India, Italy, Greece, Japan, South Korea, Taiwan and Turkey.

Each of these countries "has already demonstrated significant reductions of Iranian crude," Pompeo added. He said two of those eight "have completely ended imports of Iranian crude" and the US will continue negotiations to "get the rest to zero."

These waivers were granted "to ensure a well-supplied oil market," Pompeo said.

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Oil prices initially soared on fears that the Iran sanctions would knock the world's fifth-biggest producer offline. However, fears of a supply shortage have been eased by the Trump administration's temporary waivers for China and India and stronger oil output from Saudi Arabia and the United States.

US oil prices, which have also been hurt by worries about slowing global growth, have declined by about 17% since peaking on October 3.

Iranian President Hassan Rouhani vowed to continue oil exports Monday, saying Iran will "proudly break the unjust sanctions."

A State Department spokesperson confirmed that the US will also grant a waiver to Iraq to continue purchasing Iranian electricity.

"A waiver was granted to allow Iraq to continue to pay for electricity imports from Iran," the spokesperson said. "We are confident this will help Iraq limit electricity shortages in the South. We continue to discuss our Iran-related sanctions with our partners in Iraq."

In a move that will ratchet up pressure on Iran, SWIFT, the messaging service used by global banks, said it would suspend some of the country's banks. Mnuchin had said Friday that if the global service did not cut off designated institutions, it could be subject to sanctions.

"In keeping with our mission of supporting the resilience and integrity of the global financial system as a global and neutral service provider, SWIFT is suspending certain Iranian banks' access to the messaging system," SWIFT said in a statement. "This step, while regrettable, has been taken in the interest of the stability and integrity of the wider global financial system. Our mission remains to be a global neutral messaging provider."

The US announcement on Monday brings the total of Iranian-related targets sanctioned under the Trump administration to 900 in less than two years and represents a significant escalation of Washington's efforts to place economic pressure on the Iranian regime.

'Starve the regime'

The goal, Pompeo said Monday, is to "starve the regime" and force it to "abandon its current revolutionary course." That includes Iran's detention of Americans, its support for Hezbollah, Houthi rebels in Yemen, its involvement in Iraq and Syria, among other activities Pompeo said are destabilizing the Middle East.

Last week, Pompeo said the US wants "to restore democracy" in Iran. On Monday, the top US diplomat said that Iran "can either do a 180 degree turn from its outlaw course of action, or it can see its economy crumble."

We are intent on making sure the Iranian regime stops siphoning its hard currency reserves into corrupt investments and the hands of terrorists," Mnuchin said.

The Cabinet officials' announcement deepens a growing divide with Europe.

The EU, along with the UK, France, Germany, said Friday that the pact "is a key element of the global nuclear non-proliferation architecture and of multilateral diplomacy, endorsed unanimously by the UN Security Council."

They added that the Joint Comprehensive Plan of Action, as the deal is formally known, "is working and delivering on its goal" and "is crucial for the security of Europe, the region, and the entire world."

'Bullying is backfiring'

Iran's foreign minister said Monday that the US was defying the Security Council by re-imposing sanctions, adding that the US "bullying is backfiring."

"Today, US defied UN top court & Security Council by reimposing sanctions on Iran that target ordinary people," Foreign Minister Javad Zarif wrote on Twitter.

"But US bullying is backfiring, not just because JCPOA is important, but because the world can't allow Trump & Co. to destroy global order. The US—& not Iran—is isolated."

Today, US defied UN top court & Security Council by reimposing sanctions on Iran that target ordinary people. But US bullying is backfiring, not just because JCPOA is important, but because the world can't allow Trump & Co. to destroy global order. The US—& not Iran—is isolated. pic.twitter.com/206g1BFqbU — Javad Zarif (@JZarif) November 5, 2018

Zarif might have been anticipating Pompeo's remarks to reporters later Monday. The top US diplomat said that the reimposed sanctions "will accelerate the rapid decline" of international trade with Iran, noting that over 100 companies have withdrawn or canceled plans to do business there.

"If a company evades our sanctions regime and secretly continues" to do business with Iran "the United States will levy severe, swift penalties on it," Pompeo said, "including potential sanctions."

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"Doing business with Iran and being connected to Iran ... will ultimately be a much more painful business decision that pulling out of Iran," he promised.

Among the US targets on Monday are 92 entities owned or controlled by Ghadir Investment Company, which the US government had previously identified as an investment firm with ties to the Execution of Iman Khomeini's Order, a state-owned enterprise under direct control of Iran's Supreme Leader.

The Treasury Department also labeled 70 financial institutions with ties to Iran, including their foreign and domestic units, which have helped to funnel billions of dollars to the Islamic Revolutionary Guard Corps-Qods Force. Those firms include Bank Melli, Arian Bank, Future Bank and the Export Development Bank of Iran.

Some of the banks designated on Monday have served as "financial conduits" for the Ministry of Defense and Armed Forces Logistics and the Islamic Republic of Iran Broadcasting, according to the US government.

"This action is aimed at cutting off Iranian banks that facilitate Iran's domestic repression and foreign adventurism from the international financial system, and will highlight for the world the true nature of the regime's abuse of its domestic banking system," Sigal Mandelker, Treasury's counter-terrorism chief, said in a statement.

The Trump administration also designated more than 200 persons and vessels in Iran's shipping and energy sectors, including the Islamic Republic of Iran Shipping Lines, which is a maritime carrier, and oil transport giant National Iranian Tanker Company.

"They're the strongest sanctions we've ever imposed," said Trump en route to a rally in Georgia on Sunday evening, hours before the sanctions on Iran's energy, shipbuilding and banking sectors kicked in at midnight. "We'll see what happens with Iran," adding "they're not doing very well."