TehranWashington set Iran’s uranium ceiling at 400 kg.
The US demands Iran keep only 1 nuclear facility, refuses compensation for the February strikes, and caps frozen-asset releases at 25%, Iranian state media reported.
Iran demanded sanctions relief and compensation for bombing; the US dismissed both.
Sources: TASS
WHAT 400 KG MEANS
A weapon needs roughly 25 kg of uranium enriched to ~90% (weapons-grade). 400 kg of low-enriched material is the feedstock, not the bomb — but at 60% enrichment, the same mass yields enough fissile core for multiple devices once spun a final time.
THE JCPOA BENCHMARK
The 2015 deal capped Iran at 300 kg of uranium enriched to 3.67% — civilian reactor grade. After the US withdrew in 2018, Iran progressively breached every limit; by 2024 the IAEA reported stockpiles above 6,000 kg and enrichment up to 60%, a short technical step from weapons-grade.
WHY ONE FACILITY
Iran's program is distributed across at least four sites: Natanz (main enrichment), Fordow (buried under a mountain near Qom), Isfahan (conversion), and Arak (heavy water). Consolidating to one site collapses the redundancy that made the program strike-resistant — and makes any future inspection regime far cheaper to verify.
THE FROZEN ASSETS
Roughly $100bn in Iranian assets sit blocked across South Korean, Japanese, Iraqi, and European accounts — mostly oil-export proceeds Iran could not repatriate under US sanctions. A 25% release cap means Tehran sees ~$25bn against demands for the full balance plus war reparations.
THE BREAKOUT CONCEPT
"Breakout time" is how long Iran would need — from a given stockpile and centrifuge baseline — to produce enough weapons-grade uranium for one device. JCPOA was designed to keep breakout above 12 months. Post-withdrawal estimates collapsed it to weeks. Every kilogram and every centrifuge in the talks maps to days on this clock.
WHY COMPENSATION IS A DEAL-BREAKER
Accepting compensation for the February strikes would mean the US conceding the strikes were illegal — a precedent Washington has refused since the 1988 Vincennes downing of Iran Air 655. Iran sued at the ICJ then and won a partial settlement, but the US has never paid wartime reparations to a state it considers adversarial.