Iran has enriched uranium closer to the level required to arm nuclear missiles, according to evidence discovered at an underground facility by UN nuclear inspectors.
In its latest report on Iran's nuclear activity, the International Atomic Energy Agency (IAEA) said it had found traces of uranium enriched up to 27pc at the Fordow enrichment plant near Qom.
That is substantially below the 90pc level needed to make the fissile core of nuclear arms, but above Iran's highest-known enrichment grade of 20pc, the level from which uranium can quickly be turned into weapons-grade material.
Diplomats shown the report, which was distributed among the agency's 35 member states yesterday, said it was possible that the centrifuges may have initially "over-enriched" at the start. The IAEA said Iran claimed that the higher-grade enrichment may have happened "for technical reasons beyond the operator's control".
However, the finding will intensify concerns that Iran is using the current round of international talks to play for time.
The IAEA's report also confirmed that Iran had added a further 350 centrifuges -- capable of churning out 20pc uranium -- this year at the Fordow facility, in addition to 700 installed previously.
The disclosures came the day after the conclusion of the first direct meeting between Iran and the international community in years and will undermine confidence that a breakthrough can be reached. (© Daily Telegraph, London)