US-Iran talks to end seven months of conflict center on Iran's remaining stockpile of uranium enriched to 60 percent, estimated by the IAEA at roughly 440 kilograms before 2025-2026 strikes damaged or destroyed enrichment facilities at Natanz, Fordow, and Isfahan. Much of the material is believed buried in tunnels, with uncertain quantities surviving and no IAEA access restored since the attacks. US officials, including Vice President JD Vance, have conditioned any final agreement on concrete Iranian steps to cut enrichment capacity and dispose of the stockpile, with recent interim understandings calling for on-site dilution or removal under monitoring. Negotiations continue within a 60-day window following a preliminary memorandum, amid Iranian insistence on retaining enrichment rights.