Bucking pressure from the U.S.'s closest European allies, President Donald Trump withdrew the U.S. Tuesday from its participation in the landmark nuclear agreement world powers struck with Iran in 2015.
Trump opted not to extend sanctions relief on Iran ahead of a May 12 deadline, vowing instead to re-impose the U.S.'s nuclear-related economic penalties.
“We will be instituting the highest level of economic sanction," Trump said while announcing his decision from the White House, warning Tehran that if it "continues its nuclear aspirations it will have bigger problems than it has ever had before.”
Trump said the "horrible one-sided" agreement should have never been agreed to, claiming it "was so poorly negotiated that even if Iran fully complies, the regime can still be on the verge of a nuclear breakout in just a short period of time."
Sanctions will begin to be reimposed within 90-day and 180-day "wind-down periods," the Treasury Department said in a statement. It is unclear which sanctions fall under the appropriate time frames, but Trump's recently-seated national security advisor, John Bolton, warned that companies should not engage in any new business with Iran.
He further left the door open to new sanctions being implemented "as new information comes to light".
Following Trump's announcement, Iranian President Hassan Rouhani has indicated that Iran would seek to remain in the nuclear deal.
The decision strikes a major blow to the nonproliferation agreement that was one of former President Barack Obama's signature achievements, as well as to European leaders who had been counseling Trump against the move.
In a rare statement, Obama lashed out at Trump's announcement calling it a "serious mistake".
"Without the JCPOA, the United States could eventually be left with a losing choice between a nuclear-armed Iran or another war in the Middle East," he said, referring to the accord, which is known as the the Joint Comprehensive Plan of Action (JCPOA). "We have been safer in the years since we achieved the JCPOA, thanks in part to the work of our diplomats, many members of Congress, and our allies."
The 2015 nuclear agreement placed unprecedented restrictions on Iran's nuclear program in exchange for billions of dollars in relief from international sanctions, but Trump has consistently railed against it since he began his bid for America's highest office, repeatedly claiming it is the "worst deal" he has ever seen.
All of the U.S.'s negotiating partners -- the U.K., France, Germany, Russia, China and the EU -- had agreed that maintaining the JCPOA was the best way to reign in Iran's program.
Trump had until recently been warned against violating the nuclear accord by some of his closest advisors who have since been replaced by what analysts consider as more hawkish individuals, particularly when it comes to Iran, including Bolton and Secretary of State Mike Pompeo.
Trump said the U.S. will be "working with our allies to find a real, comprehensive and lasting solution to the Iranian nuclear threat", but the specifics on any such effort are unclear.
Trump himself acknowledged the difficulties in negotiating a new agreement with Iran.
"Iran’s leaders will naturally say that they refuse to negotiate a new deal; they refuse. And that's fine. I'd probably say the same thing if I was in their position," he said, but claimed "the fact is they are going to want to make a new and lasting deal".
UN Secretary General Antonio Guterres voiced deep concern over Trump’s announcement, calling the JCPOA “a major achievement in nuclear non-proliferation and diplomacy” that has benefited the region and the international community.
“It is essential that all concerns regarding the implementation of the Plan be addressed through the mechanisms established in the JCPOA,” he said in a statement.
