---
title: "Uranium-233: Thorium-Bred Fissile Fuel | Model Diplomat"
description: "Uranium-233 is a fissile isotope bred from thorium-232, central to India's three-stage nuclear programme. See how U-233 differs from plutonium-239 and U-235."
url: "https://modeldiplomat.com/learn/glossary/uranium-233"
---

[New](https://modeldiplomat.com/)

#

Model Diplomat Research Team · Last reviewed June 22, 2026

TL;DR

- Uranium-233 is a fissile isotope of uranium bred from thorium-232 by neutron capture, used as nuclear fuel and central to India's thorium-based reactor programme.
- Why is uranium-233 central to India's nuclear programme?
- How does uranium-233 differ from plutonium-239 and uranium-235?
- Is uranium-233 a proliferation risk?
- Why has the thorium-U-233 cycle not been commercialised?

[Civil Service & Diplomatic Exams](https://modeldiplomat.com/learn/civil-services/glossary)Updated June 22, 2026

Uranium-233 is a fissile isotope of uranium bred from thorium-232 by neutron capture, used as nuclear fuel and central to India's thorium-based reactor programme.

Go beyond the definition

## Research Uranium-233 like a delegate

Model Diplomat's AI drafts position papers, speeches, and country research with real sources — built for MUN and politics students.

## Research it like a delegate

Research on modeldiplomat.com

## Ask a follow-up about Uranium-233

Open a cited briefing in Model Diplomat search — timelines, positions, and sources you can use in committee or exam answers.

[Start research on Uranium-233](https://modeldiplomat.com/search?q=Explain%20Uranium-233%20%E2%80%94%20key%20dates%2C%20actors%2C%20positions%2C%20and%20sources)

Example

In 1996 India's Bhabha Atomic Research Centre commissioned the KAMINI reactor at Kalpakkam, the world's only operating reactor fuelled by uranium-233, demonstrating the thorium-bred fissile cycle.

Keep learning

## Go deeper than the definition

[Explore all Civil Service & Diplomatic Exams lessons](https://modeldiplomat.com/learn/civil-services)[Test yourself with a quiz](https://modeldiplomat.com/learn/glossary/quiz/civil-services)

## Take Uranium-233 beyond the glossary

Ask the AI research engine built for diplomacy — get briefings, position papers, and speeches with sources you can cite in committee.