Why in News:

• Iran has started enriching uranium up to 20% at an underground facility and seized a South Korean-flagged oil tanker in the crucial Strait of Hormuz, further escalating tensions in West Asia between Tehran and the West.

What is enrichment of uranium?

• Natural uranium consists of two different isotopes – nearly 99% U-238 and only around 0.7% of U-235.
• U-235 is a fissile material that can sustain a chain reaction in a nuclear reactor.
• Enrichment process increases the proportion of U-235 through the process of isotope separation (U-238 is separated from U-235).
• For nuclear weapons, enrichment is required upto 90% or more which is known as Highly Enriched Uranium/weapons-grade uranium.
• For nuclear reactors, enrichment is required upto 3-4% which is known as Low Enriched Uranium/reactor-grade uranium.

Additional Information

Joint Comprehensive Plan of Action

• The Iran nuclear deal framework was a preliminary framework agreement reached in 2015 between the Islamic Republic of Iran and a group of world powers: the P5+1 (the permanent members of the United Nations Security Council—the United States, the United Kingdom, Russia, France, and China—plus Germany) and the European Union.
• In May 2018, the USA abandoned the deal criticising it as flawed and reinstated and tightened its sanctions.

Reference:

1. https://www.thehindu.com/news/international/iran-says-it-begins-20-uranium-enrichment-amid-us-tensions/article33493313.ece