BROKERED by the Obama White House and signed by seven world powers, the Iran nuclear deal aimed to reduce the country's ability to produce nuclear weapons.
However, Donald Trump withdrew from the deal earlier this month which he called a "horrible, one-sided deal".
What does the Iran nuclear deal entail?
The Iran nuclear deal was an agreement between the Islamic Republic and a group of world powers aimed at scrapping the Middle Eastern country's nuclear weapons programme.
The deal saw Iran agree to eliminate its stockpile of medium-enriched uranium by 98 per cent.
Enriched uranium is a critical component for making nuclear weapons and in nuclear power stations and by curbing the amount Iran produce is a way to curb the number of weapons produced.
As part of the agreement, Iran also agreed to only enrich their uranium up to 3.67 per cent over the next 15 years and they agreed to reduce their gas centrifuges for 13 years.
Gas centrifuges are used to separate different types of uranium which allows specific types to then be used to manufacture nuclear weapons or generators.
Iranian nuclear facilities were limited to a single facility with only first-generation centrifuges for 10 years and other nuclear facilities had to be converted into other use.
In addition, they were barred from building any more heavy-water faculties - a type of nuclear reactor which uses heavy water (deuterium oxide) as a coolant to maintain temperatures in the reactor.
Also under the agreement, the International Atomic Energy Agency was granted regular access to all Iranian nuclear facilities to ensure Iran maintains the deal.
The deal said that if Iran abides by the deal it would receive relief from the US, European Union, and the United Nations Security Council on all nuclear-related economic sanctions.
Which world powers signed it?
- Islamic Republic of Iran
- China
- France
- Russia
- United Kingdom
- United States of America
- Germany
- The European Union
When was it agreed?
The agreement was reached on July 14, 2015, and the world powers signed it in Vienna.
It followed years of negotiations which started in 2013.
The nuclear deal followed the Joint Plan of Action which had temporarily frozen parts of Iran's nuclear sanctions as the countries worked towards a long-term agreement.
It appeared that US President Donald Trump would follow through on his threats as the reported that he told his French counterpart Emmanuel Macron that he plans to announce the withdrawal of the US from the deal, according to a person briefed on the conversation.
Trump had repeatedly threatened to withdraw from the deal, which he has called “ridiculous” as well as "insane" and earlier set a May 12 deadline for deciding whether to pull out.
It is so far uncertain on just how the withdrawal will work in practical terms.
Just days before Trump announced his decision, Foreign Secretary Boris Johnson appealed to Trump on Fox & Friends not to rip up the agreement, urging him not to "throw the baby out with the bathwater".
On July 23 2018, Trump's war of words with Iran escalated once more, as he threatened the Islamic Republic if they did anything to hard the United States.
The argument was triggered the day before by US Secretary of State Mike Pompeo, when he compared Iran to the mafia.
What is the relationship like between the US and Iran now?
Iran announced it intends to smash the strict uranium stockpile limits set under the nuclear deal it struck with the world's leading powers.
The hardline country's shock statement is another blow to a pact already crumbling since the US’s high-profile withdrawal.
"Today the countdown to pass the 300 kilograms reserve of enriched uranium has started and in 10 days time we will pass this limit," said Iran's atomic energy organisation spokesman Behrouz Kamalvandi.
"This is based on the Articles 26 and 36 of the (nuclear deal), and will be reversed once other parties live up to their commitments."
Kamalvandi acknowledged the country has already QUADRUPLED its production of low-enriched uranium.
The news is bound to ramp up tensions between Iran and the West already at breaking point following the shock bomb attack on two tankers in the Gulf of Oman.
Many international observers believe the attack was an act of "revenge" by Iran after the White House imposed crippling economic sanctions after Donald Trump pulled out of the nuclear deal.
Just last month, Iranian President Hassan Rouhani announced his country would stop observing restrictions on its stocks of enriched uranium and heavy water agreed under the 2015 deal.
What is the Iran nuclear deal and what happens if it collapses?
The deal is an arrangement between the Islamic Republic and a group of world powers for Iran to abandon its nuclear programme.
Officially it is known as the The Joint Comprehensive Plan of Action(JCPOA).
It saw the Middle Eastern nation agree to reduce its stockpile of medium-enriched uranium by 98 per cent.
Enriched uranium is essential for developing nuclear weapons and power stations.
As part of the agreement Iran also agreed to only enrich their uranium up to 3.67 per cent over the next 15 years.
In addition they were barred from building any more heavy-water faculties - a type of nuclear reactor which uses heavy water (deuterium oxide) as a coolant to maintain temperatures in the reactor.
Also under the agreement the International Atomic Energy Agency was granted regular access to all Iranian nuclear facilities to ensure Iran maintains the deal.
The deal said that if Iran abides by it the nation would receive relief from the US, European Union, and the United Nations Security Council on all nuclear-related economic sanctions.
The agreement was reached on July 14 2015 and the world powers signed it in Vienna.
Iran, China, France, Russia, UK, USA, Germany and the EU all signed up to the deal.
If the deal collapses it initially probably means reimposing oil-related sanctions on Iran that were lifted under the terms of the agreement.
In May 2019 Trump withdrew from the 2015 nuclear agreement which he called a "horrible, one-sided deal", saying it did not address Iran's ballistic missile activities and check in its regional behaviour.
The US has now threatened to impose the "strongest sanctions in history" against Iran.
Secretary of State Mike Pompeo laid out 12 demands for Iran and said relief from economic sanctions would only come when Washington had seen tangible shifts in Iran's policies.
He warned: "The sting of sanctions will be painful if the regime does not change its course from the unacceptable and unproductive path it has chosen to one that rejoins the league of nations."
His demands came just weeks after the US pulled out of an international nuclear deal with Iran and threatened to hold those doing prohibited business in Iran to account.
Pompeo said a stronger pact should require that Iran stop enrichment of uranium, which was allowed within strict limitations under the previous deal.
Iran would also have to walk away from core pillars of its foreign policy, including its involvement in Syria, Yemen, Lebanon and Afghanistan.
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What is the timeline of Iran's nuclear progression?
- 1970s - Iran develops a nuclear technology after the U.S. Atoms for peace programme began providing assistance to them
- 1979 - The Iranian Revolution took place and the country's nuclear programme fell into disarray
- 1980s - Iran restarts its nuclear programme with assistance from Pakistan. Iran starts pursuing a nuclear fuel cycle by mining uranium
- 2002 - An Iranian dissident group publicly reveal the existence of two secret nuclear facilities, the Arak heavy-water facility and the Natanz enrichment facility
- 2003 - Iranian President Mohammad Khatani acknowledges the existence of the facilities and claims they were "small-scale enrichment experiments"
- May 2003 - Iran allows IAEA inspectors to visit the Kalaye Electric Company but refused to let them take samples
- June 2003 - Faced with the prospect of being referred to the UN security council enters into diplomatic negotiations with France, Germany and the UK. The USA refuses to be involved
- Later in June Iran agreed to fully cooperate with the IAEA and in October allows them to take samples
- 2004 - Iran signs the Paris Agreement and suspends enrichment and conversion activities including manufacturing, testing and installing
- August 2005 - Mahmoud Ahmadinejad is elected president of Iran and accuses the Paris Agreement negotiators of treason. Talks fall apart
- February 2006 - Iran resumes enrichment at Natanz and is referred to the UN Security Council
- July 2006 - UN security council passes its final resolution demanding Iran stops uranium enrichment and processing
- 2006 - 2010 - A number of resolutions are passed against Iran by the UN
- March 2013 - The USA began a series of talks with Iran
- June 2013 - Hassan Rouhani was elected as president of Iran and calls for negations with Europe
- September 2013 - Obama and Rouhani have their first telephone conversation and US secretary of state John Kerry meets with the Iranian foreign minister
- November 24 2013 - After several rounds of negotiation the Joint Plan of Action is agreed as an interim agreement
- July 24 2015 - The Iran Nuclear Deal is signed in Vienna, Austria
- April 30 2018 - The US and Israel accuse Iran of covertly continuing the development of nuclear weapons
- May 8 2018 - President Donald Trump announces the US will withdraw from the agreement - while European leaders and Russia said they would fight for its survival
- July 23 2018 - President Trump issues dramatic warning to Iran saying the Islamic Republic would suffer "historic consequences" if it threatened the United States.
- May 8 2019 - Iran's President Hassan Rouhani announced it would would reduce its "commitments" to the deal, but not fully withdraw including keeping enriched uranium stocks in the country rather than sell them abroad.
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