Donald Trump boasted early Tuesday morning that he had snapped 'biting sanctions' back on Iran as he reset the Middle East's most vexing potential hazard.

'The Iran sanctions have officially been cast. These are the most biting sanctions ever imposed, and in November they ratchet up to yet another level,' the president tweeted.

'Anyone doing business with Iran will NOT be doing business with the United States. I am asking for WORLD PEACE, nothing less!' he added.

Iran's president slammed the United States after the White House re-imposed a wave of tough, unilateral sanctions at midnight.

The U.S. brought back into effect harsh penalties that had been lifted under Barack Obama's multi-party nuclear agreement that Trump abandoned in May.

Scroll down for video

Donald Trump snapped bace unilateral sanctions against Iran at midnight, and tweeted that nations will have to choose between doing business with the Islamist nation and trading with the United States

President Hassan Rouhani described the measures as 'psychological warfare' aimed at sowing division among Iranians

'I am asking for WORLD PEACE, nothing less!' Trump tweeted

Trump said he was open to reaching a more comprehensive deal with Iran 'that addresses the full range of the regime's malign activities, including its ballistic missile program and its support for terrorism.'

But Iranian President Hassan Rouhani described the measures as 'psychological warfare' aimed at sowing division among Iranians.

'If you're an enemy and you stab the other person with a knife, and then you say you want negotiations, then the first thing you have to do is remove the knife,' the Iranian leader said in an interview on state television.

'They want to launch psychological warfare against the Iranian nation,' Rouhani said. 'Negotiations with sanctions doesn't make sense.'

The first of two rounds of US sanctions kicked in overnight, targeting Iran's access to US banknotes and key industries, including cars and carpets.

Iranians are already seeing the effects of the sanctions, with Iran's rial currency losing around half its value since Trump announced the US would withdraw from the 2015 nuclear accord.

Many large European firms are leaving Iran for fear of US penalties, and Trump warned of 'severe consequences' against firms and individuals that continued to do business with Iran.

The impact of the return of sanctions has ramped up tensions inside Iran, which has seen days of protests and strikes in multiple towns and cities over water shortages, high prices and wider anger at the political system.

Severe reporting restrictions have made it impossible to verify the swirl of claims coming through social media.

Trump's contempt for the nuclear deal dates back to his time as presidential candidate and on May 8, he made good on a pledge to pull America out of the international agreement.

President Trump said Monday that he will fully enforce sanctions due to be reimposed against Iran as he signed an executive order announcing his intent. Pictured, Trump signing a proclamation withdrawing the US from the Iran nuclear agreement in May at the White House

He blasted the agreement yet again Monday, calling it a 'horrible, one-sided deal (that) failed to achieve the fundamental objective of blocking all paths to an Iranian nuclear bomb.'

The unilateral withdrawal came despite other parties to the agreement - Britain, China, France, Germany, Russia and the EU - pleading with Trump not to abandon the pact.

Washington's so-called 'snapback' sanctions were reinstated against Tehran at 12.01am EDT on Tuesday. A second wave will go into effect on November 4.

In an executive order Monday, Trump said the sanctions seek to pile financial pressure on Tehran to force a 'comprehensive and lasting solution' to Iranian threats, including its development of missiles and regional 'malign' activities.

'The United States is fully committed to enforcing all of our sanctions, and we will work closely with nations conducting business with Iran to ensure complete compliance,' Trump said in a statement that trashed the Iran nuclear pact as a 'horrible' and 'one-sided' agreement.

'Individuals or entities that fail to wind down activities with Iran risk severe consequences.'

The president signed the executive order from his Bedminster, New Jersey, property.

He did so behind closed doors with reporters miles away after the White House told journalists covering him that he would not make any public appearances that day.

Instead, the president issued a statement that labeled the Iran nuclear pact 'a horrible, one-sided deal, failed to achieve the fundamental objective of blocking all paths to an Iranian nuclear bomb, and it threw a lifeline of cash to a murderous dictatorship that has continued to spread bloodshed, violence, and chaos.'

Trump withdrew the United States from the Iran deal, formally known as the Joint Comprehensive Plan of Action, on May 8, starting a ticking clock for the sanctions on Tehran to be reimposed.

He has repeatedly denounced the deal reached under his White House predecessor, Barack Obama, as one-sided in Iran's favor. He promised as a candidate to tear it up.

Secretary of State Mike Pompeo, speaking with reporters returning with him from an Asian trip, said Monday morning that sanctions are 'an important part of our efforts to push back against Iranian malign activity' and the U.S. would enforce the restrictions on certain Iranian goods.

Starting this week, Washington will bring back sanctions on Iran's purchases of U.S. dollars, its trade in gold and precious metals, and its dealings with metals, coal and industrial-related software.

The United States has told other countries they must halt imports of Iranian oil starting in early November or face U.S. financial measures.

President Trump urged all nations and corporations 'to take such steps 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' in the statement that served as a substitute for on-camera remarks.

His executive order immediately targets Iran's automotive, energy, shipbuilding and precious metals industries and begins a wind-down period for the acquisition, sale and transport of petroleum and petrochemical products.

The directive states that the punishments are intended to 'advance the goal of applying financial pressure on the Iranian regime in pursuit of a comprehensive and lasting solution to the full range of the threats posed by Iran' which include its missile development and support for terror groups as well as a 'network and campaign of regional aggression' and 'malign activities of the Islamic Revolutionary Guard Corps and its surrogates.'

Trump has forcefully denounced Iran's 'DEMENTED WORDS OF VIOLENCE & DEATH' toward the U.S. and at the end of July warned Iran not to threaten the United States or plan to 'SUFFER CONSEQUENCES THE LIKE OF WHICH FEW THROUGHOUT HISTORY HAVE EVER SUFFERED BEFORE.'

That was after Rouhani warned the US that war with Iran 'is the mother of all wars' and said Trump stop 'playing with the lion's tail,' with the stark pledge of or 'else you will regret it.'

Still, the Trump administration has said the president would be willing to negotiate a new deal with Tehran under the right conditions. However, Iran should not expect relief sanctions in the interim.

The president said in a weekend tweet that the ball is in Tehran's court.

'I will meet, or not meet, it doesn't matter - it is up to them!' he said of a potential meeting with Rouhani.

National Security Advisor John Bolton said Monday that Trump stands by his offer and it is Tehran that is refusing to meet with the American president.

'I think he was very serious about it. If the Ayatollah's want to get out from under the squeeze, they should come and sit down. The pressure will not relent while the negotiations go on, much as in the case of the maximum pressure campaign against North Korea,' Bolton said.

Iran's Foreign Minister Mohammad Javad Zarif said Monday that Trump has 'isolated' America with his position on sanctions. The United States' other negotiating partners, including France and Germany, remain in the deal.

'Of course, American bullying and political pressures may cause some disruption, but the fact is that in the current world, America is isolated,' said Zarif, who played a lead role in 2015 talks, as he downplayed the hit his country will endure as a result of the sanctions.

EU diplomatic chief Federica Mogherini in a statement jointly signed with the foreign ministers of Britain, France and Germany, shared her dismay at Trump's order that will seal the break down of the deal on Monday.

'We deeply regret the re-imposition of sanctions by the U.S.' the statement said. 'We are determined to protect European economic operators engaged in legitimate business with Iran.'

Iran's Foreign Minister Mohammad Javad Zarif (pictured) said it was hard to imagine negotiating with the man who tore up an agreement on which Iran and world powers had spent the 'longest hours in negotiating history' as he claimed that America is 'isolated' as a result of the sanctions implimentation

Rouhani said last week that Trump's repudiation of the deal was illegal and Iran would not yield to Washington's renewed campaign to strangle Iran's vital oil exports.

Iran will ease foreign exchange rules, state TV reported on Sunday, in a bid to halt a collapse of the rial currency, which has lost half its value since April due to fears about the return of the sanctions.

Iran has seen days of protests and strikes directed at the country's iron-fisted rulers.

A senior administration official told reporters during a Monday morning call that the blame 'lies with the Iranian regime' that has squandered the country's' resources and oppressed its people.

Officials on the call would not endorse regime change in Tehran and refused to say that the inherent purpose of the United States' punishing actions was to force the collapse the Iranian economy.

A senior official hinted at the end game, however, telling press: 'We are very intent on using these financial sanctions to great economic leverage.'

Referring to the sporadic protests in Iranian cities in his Monday avail, Pompeo said: 'The Iranian people are not happy - not with the Americans but with their own leadership. They're unhappy with the failure of their own leadership to deliver the economic promises that their leadership promised them.'

Pompeo said the United States wants 'the Iranian people to have a strong voice of who their leadership will be,' although he stopped short of calling for regime change in Tehran.

He later said in a message on Twitter that the United States was 'deeply concerned about reports of Iranian regime´s violence against unarmed citizens' and urged respect for human rights.

Protests broke out on Sunday for a sixth night in Iranian cities, including Kazeroon in the south, according to social media. Authorities reported the first fatality among protesters, with the shooting of a man in Karaj, west of Tehran. But they denied security forces were involved, Iranian news agencies reported

The protests have often begun with slogans against the high cost of living and alleged financial corruption but quickly turned into anti-government rallies.

Pompeo said it would require 'enormous change' by Iran to get out from under renewed U.S. sanctions. 'They have got to behave like a normal country,' he said, describing Iranian leaders as 'bad actors.'

He alluded to Trump's suggestion last week of the potential for future negotiations with Tehran, a notion that senior Iranian officials quickly rejected.

'We are happy to talk if there's an arrangement that is appropriate, that could lead to a good outcome,' he said. 'Perhaps that will be the path the Iranians choose to move down with. There´s no evidence to date of their desire to change to change their behavior.'