The central points at issue are:
- Iran's "right" to enrich. If uranium is processed to 5 per cent purity, it can be used to fuel nuclear power stations. If enriched to 90 per cent, it reaches weapons grade and becomes the essential material for a nuclear bomb. The problem is that once you master the technology for 5 per cent, you can also reach 90 per cent, given enough time.
- Iran correctly points out that the nuclear non-proliferation treaty allows states to enrich for peaceful purposes. And it says that running nuclear power stations is the only goal. But America and its allies - and other countries as well - do not trust this assurance. The United Nations has passed six resolutions ordering Iran to halt enrichment.
- So this is a dispute about whether Iran's "right" to this technology is acknowledged or not. Privately, diplomats point to a solution: Iran is allowed to enrich but only to 5 per cent - and intrusive safeguards are introduced to ensure it keeps to the deal. The "enrichment with safeguards" formula would probably be the core of any agreement.