Context:

• Iran said it would abandon limitations on enriching uranium, refusing to adhere to the 2015 nuclear deal it signed with six major powers, but would continue to cooperate with the UN nuclear watchdog.
• Iran’s announcement comes after its top security and intelligence commander, Major General Qassem Soleimani, was killed in a US drone attack in Baghdad

Timeline:

• Iran ratified the Nuclear Non-Proliferation Treaty (NPT) in 1970, and planned to expand its nuclear power.
• After the Islamic Revolution, these plans were discontinued, and in the late 1980s, Iran established an undeclared nuclear weapons program called the AMAD project. 
• In 2003, under international pressure, Iran halted the program, and signed an Additional Protocol to its NPT safeguards agreement, giving the International Atomic Energy Agency (IAEA) greater powers in verifying the program.
• In 2006, the US, Russia and China joined Britain, France and Germany to form the P5+1 group of nations trying to persuade Iran to curb its nuclear program.
• In 2009, under President Barack Obama, the US conducted extensive one-on-one talks with Iran’s top nuclear negotiator.
• In 2013, Iran and the six powers announced an interim agreement that temporarily curbed Tehran’s nuclear program and unfreezed some Iranian assets, setting the stage for extended negotiations on a comprehensive nuclear accord.
• in 2015, the Iran nuclear deal (formally the Joint Comprehensive Plan of Action) was signed between Iran and the P5 (the five permanent members of the UN Security Council) plus Germany and the European Union.

Joint Comprehensive Plan of Action or Nuclear deal:

• Under JCPOA, Iran agreed to eliminate its stockpile of medium-enriched uranium, cut its stockpile of low-enriched uranium by 98%, and reduce by about two-thirds the number of its gas centrifuges for 13 years. 
• For the next 15 years Iran will only enrich uranium up to 3.67%. 
• Iran also agreed not to build any new heavy-water facilities for the same period of time. 
• Uranium-enrichment activities will be limited to a single facility using first-generation centrifuges for 10 years.
•  Other facilities will be converted to avoid proliferation risks. 
• To monitor and verify Iran’s compliance with the agreement, the International Atomic

What will Iran get in return?

• Iran will receive relief from U.S., European Union, and United Nations Security Council nuclear-related sanctions.

Reason behind the US decision to withdraw from Nuclear deal:

• Mr. Trump’s decision is not about Iran acquiring nuclear weapons. If it was the actual concern, it would have supported a deal that closes the path towards nuclear weapons for Iran.
• Instead, the bigger concern for Mr. Trump as well as Washington’s closest allies in West Asia — Israel and Saudi Arabia — is Iran’s re-accommodation in the global economic mainstream.
• They fear that if Iran’s economic profile rises, it will embolden it to increase its regional presence, posing a strategic threat to the interests of the U.S.-Saudi-Israel axis.

How does it affect India?

• The reintroduction of sanctions against Iran is bad news. Iran is now India’s third largest source of oil. 
• Apart from supply disruptions, a further surge in crude prices will worsen India’s current account imbalance and fuel inflation, at a time when the economy is just beginning to show signs of returning to a high growth trajectory.
• For global corporations too, there will be considerable pain. For example, there are said to be around 200 French companies operating in Iran and some like Renault have plants there. They will now have a 90-day period to wind down operations. 
• India’s Chabahar port project in Iran, which was just showing signs of moving forward, could be in trouble.

Conclusion:

• US-Iran ties have continued to worsen since President Donald Trump unilaterally withdrew from the 2015 nuclear deal and imposed crippling sanctions on Iran.
• Relations between the two countries first became acrimonious during the 1979 Iranian Revolution, which brought Iran’s pro-West monarchy to an end, and replaced it with an Islamic Republic.