@DrPrunesqualer you say "The Islamic Republic has always disavowed any interest in nuclear weapons" to which I say, Yes but no one trusts them not to do so.
Obama didn't trust them not to develop nuclear weapons, Trump doesn't trust them, the EU don't trust them and the UK government don't trust them. They all say: Iran must never be allowed to develop nuclear weapons.
We're not stupid. If they don't have any interest in nuclear weapons why were they fighting so hard for the right to develop nuclear capability. They didn't need to enrich uranium levels to 60% for any other reason - that was a threat.
As the Stockholm International Peace Research Institute noted in 2021:
Once it has been enriched beyond 20 per cent, uranium enters a different nuclear materials safeguards accounting category: highly enriched uranium (HEU). Although under the Nuclear Non-Proliferation Treaty (NPT) it is legal for any country to produce HEU, the JCPOA limits Iran’s uranium enrichment to 3.67 per cent.
Iran’s decision has also inevitably drawn international attention because it brings the country so close to producing 90 per cent-enriched uranium, which is generally considered weapons-grade.
Uranium enriched to 60 per cent cannot be used to make a useful nuclear explosive device, and Iran has no other realistic use for this material.
Nevertheless, 60 per cent was not an arbitrary choice. Cascades of centrifuges are designed to enrich uranium in steps; Iran’s centrifuges are likely set up to enrich up to 20 per cent, from 20 to 60 per cent, and from 60 to 90 per cent.
Assuming the 60 per cent-enriched uranium is stored in the form of uranium hexafluoride (UF6) gas—and there would be no point in Iran converting it to any other chemical form—the enrichment step from 60 per cent-enriched to weapons-grade uranium is very short.
www.sipri.org/commentary/essay/2021/why-iran-producing-60-cent-enriched-uranium