International Relations GS 2 In the news 5 times

Uranium Enrichment

Technical and Proliferation Concepts

Natural uranium contains ~0.7% U-235 (the fissile isotope). Enrichment increases the concentration of U-235 through centrifuge cascades (gaseous diffusion is largely obsolete).

Key details

Low-Enriched Uranium (LEU): 3–5% U-235 — used in civilian power reactors (Light Water Reactors).
Highly Enriched Uranium (HEU): 20%+ U-235 — used in research reactors and nuclear weapons (weapons-grade is typically 90%+).
The 2015 JCPOA (Joint Comprehensive Plan of Action) capped Iran's enrichment at 3.67% U-235 and its LEU stockpile at 300 kg.
Iran progressively violated JCPOA caps from 2019 onward after US withdrawal; by mid-2025 it had enriched to 60%.
60% enrichment is well above civilian need (LEU) and technically close to weapons-grade; it significantly reduces the "breakout time" (time needed to produce enough weapons-grade material for one bomb).
IAEA verification requirement under the CSA: HEU stockpiles must be verified at least once a month (every 30 days).

In the news

● Tracked since February 27, 2026 · last seen June 26, 2026 · updates as the daily brief publishes

26 Jun '26

Iran Nuclear Deal: IAEA Inspector Access, Uranium Enrichment, and Non-Proliferation Framework

International Relations

17 May '26

US-Iran Nuclear Talks Stall as Enrichment and Stockpile Demands Remain Unresolved

International Relations

09 Apr '26

Iran's Uranium Enrichment as a "Necessary" Condition for US Talks: Islamabad Negotiations

International Relations

09 Apr '26