The UN nuclear watchdog has found uranium enriched to 84% in Iran - very close to weapons grade - diplomats said on Monday, while the watchdog said that it was in talks with Tehran about recent findings there. Iran has been enriching uranium to up to 60% purity since April 2021. Three months ago, it started enriching to 60% at a second site, Fordow, which is dug into a mountain. Weapons grade is around 90%. Two diplomats told Reuters the International Atomic Energy Agency, which inspects Iran's nuclear facilities, had detected uranium enriched to 84%, confirming an initial report late on Sunday by Bloomberg News. "The issue is whether it was a blip in the reconfigured cascades or deliberate. The agency has asked Iran for an explanation," one of the diplomats told Reuters. Earlier this month, the IAEA criticized Iran for failing to inform it of a "substantial" change to the interconnections between the two cascades, or clusters, of centrifuges enriching uranium to up to 60% at Fordow. Several diplomats said the change meant Iran could quickly switch to a higher enrichment level. Those rearranged cascades are the ones the first diplomat was referring to. The United States in 2018 pulled out of the 2015 nuclear deal between Iran and major powers that had lifted sanctions against Tehran in exchange for curbs on its nuclear activities. Iran responded to the reimposition of US sanctions by breaching those restrictions and going well beyond them, to the point that IAEA chief Rafael Grossi has said the deal is now an "empty shell". Still no IAEA report Prospects for reviving the deal are dim, diplomats say, with tensions between Iran and the West high over protests in Iran, the war in Ukraine, and Iran's continued nuclear advances eroding the time it would need to produce a nuclear bomb if it chose to. Iran denies having such intentions. "The IAEA is aware of recent media reports relating to uranium enrichment levels in Iran," the IAEA said on Twitter on Sunday. "The IAEA is discussing with Iran the results of recent Agency verification activities and will inform the IAEA Board of Governors as appropriate." The IAEA, which inspects Iran's nuclear facilities, flags significant developments in Iran's activities either in ad hoc reports to the 35-nation Board of Governors or regular quarterly ones issued before board meetings. Diplomats said on Monday that the IAEA so far had not issued any such report. The next quarterly Board of Governors meeting begins on Monday, March 6, and quarterly reports are usually issued in the week before a meeting. "So far, we have not made any attempt to enrich above 60%. The presence of particles above 60% enrichment does not mean production with an enrichment above 60%," the spokesperson for Iran's Atomic Energy Organization, Behrouz Kamalvandi, said on Monday, according to the official IRNA News agency.