President Trump has refused to recertify the Iran nuclear deal, calling it “one of the worst” and most “one-sided” agreements America has ever entered in to.
The landmark Obama-brokered deal limited Iran’s nuclear capability in return for the lifting of some sanctions.
Mr Trump savaged Iran’s “rogue regime” in a speech at the White House, in which he also imposed extra sanctions on the country’s Islamic Revolutionary Guard.
He blamed Iran for spreading “death, destruction and chaos all around the world” and said it had committed multiple infringements of the deal.
However, the President’s decision does not mean the pact will be scrapped immediately, instead it will be forwarded to the US Congress.
It will then have 60 days to decide whether to reimpose sanctions or modify the laws on America’s involvement in the pact, known as the Joint Comprehensive Plan of Action.
“We will not continue down a path whose predictable conclusion is more violence more terror and the very real threat of Iran’s nuclear breakout,” said President Trump.
He said the deal had “many flaws” and warned: “if we are not able to reach a solution working with Congress and our allies, then the agreement will be terminated”.
The President also used his speech to criticise Iran’s non-nuclear activities, such as its ballistic missile programme, and said it had supported Syria’s President Assad and Lebanon’s Hezbollah.
He said Iran-backed attacks had killed many Americans over the years, and that the country had “harboured terrorists” after the 9/11 attacks.
The original sanctions on Iran had included a freezing of financial assets, weapons sales and crude oil exports.
Under the restrictions, the country lost more than a hundred billion dollars in oil revenue between 2012 and 2016 alone.
On implementation day in January 2016, the White House said Iran had completed all the steps needed to ensure its nuclear programme was exclusively peaceful.
This included shipping 25,000 pounds of enriched uranium out of the country, and the dismantling and removing of two-thirds of its centrifuges, used to enrich uranium.
Russia said that if the US pulled out entirely, it would damage the current atmosphere of security, stability and non-proliferation around the world.
Russia, along with Britain, France, Germany, China and the European Union are also signatories to the deal.
The EU’s foreign policy chief, Federica Mogherini, reacted swiftly to Mr Trump’s decision and said it was not for any one country to terminate the deal.
However, Israeli Prime Minister Benjamin Netanyahu congratulated the President for “boldly confronting Iran’s terrorist game” and urged other countries to follow his lead.