Tillerson further repeated a defunct USA accusation that Iran's nuclear program is not peaceful, claiming that the deal "only delays their goal of becoming a nuclear state".
Last week, the Treasury Department sanctioned Sohrab Soleimani, the younger brother of Gen. Qassem Soleimani, for human rights abuses he committed as head of Iran's notorious Evin prison. Iran was required to give up nearly all of its enriched uranium, which can be used to make a nuclear weapon, and is subject to ongoing inspections by the International Atomic Energy Agency. "An unchecked Iran has the potential to travel the same path as North Korea and to take the world along with it".
Iran's Foreign Minister Mohammad Javad Zarif on Thursday criticised "worn-out" U.S. accusations that it was seeking a nuclear weapon to threaten the region and the world. The statement came following numerous denials by Iran regarding the accusations made by the US.
The nuclear deal, known as the Joint Comprehensive Plan of Action, was signed in Vienna in July 2015.
Secretary of State Rex Tillerson said the United States is now assessing the Iran nuclear deal because the country is the world's leading state sponsor of terrorism.
The nuclear agreement, negotiated during Barack Obama's presidency, placed limitations on Iran's nuclear program in exchange for lifting economic sanctions against Iran.
Britain could join U.S. against Assad's regime in Syria
The Turkish government said autopsies on victims brought over the border confirmed chemical weapons had been used. Former foreign minister Alistair Burt asked Johnson whether the government felt bound by a previous vote in 2013.
The agreement to limit Iran's nuclear programme was widely denounced by Republicans, who tried to block the deal in the US Senate.
He gave no indication of how long the review would take or what the likely outcome would be.
Tillerson lambasted the country for "supporting the Assad regime, even as it commits atrocities against its own people".
"Iran is the world's leading state sponsor of terrorism", Tillerson began. "And is responsible for intensifying multiple conflicts and undermining U.S. interests in countries such as Syria, Yemen, Iraq and Lebanon, and continuing to support attacks against Israel". It is the first update under the Trump administration.
Iran helped to create and continues to fund Hezbollah, the Lebanese military and political organization which the United States has listed as a terrorist organization.
The Trump administration is considering re-imposing a massive set of economic sanctions on Iran that were lifted by the Obama administration as part of the landmark nuclear agreement that gave Tehran billions in economic support, according to US officials who told the Washington Free Beacon that Iran's military buildup and disregard for global law could prompt USA reprisal.
Trump Nominates Scott Brown As US Ambassador To New Zealand
The White House announced today that Scott Brown was the President Donald Trump's pick to serve as the Ambassador to New Zealand. Brown moved his residency to the Granite State three and a half years ago before launching a Senate run in New Hampshire in 2014.
In a speech watched by Prince Saud al-Faisal, ministers and the ambassador, Mr Tillerson hailed "a successful new chapter" for relations between Saudi Arabia and the USA, and their "shared economic and strategic goals".
White House press secretary Sean Spicer talks to the media during the daily press briefing at the White House in Washington, Monday, April 10, 2017. "The evidence is clear Iran's provocative actions threaten the United States, the region and the world".
North Korea has carried out a number of missile tests in defiance of United Nations sanctions and the hostile rhetoric between Pyongyang and Washington has steadily escalated.
Mr Trump heavily criticised the Saudi government on Twitter before his election victory but has since remained silent, while fostering a close relationship and excluding the country from his attempted immigration bans.
North Korea said it may test missiles on a weekly basis, and warned of "all-out war" if the USA takes military action.
Donald Trump congratulates Erdogan after Turkey referendum win
Electoral board head Sadi Guven said the objections would be evaluated later on Wednesday. Sunday's referendum ends debate on forging a stronger presidency, he told supporters.