Iran has made 6.5 kg (14 lb) of uranium enriched to up to 60%, the government said on Tuesday, detailing a move that rattled the country's nuclear talks with world powers by taking the fissile material a step towards nuclear weapons grade of 90%.

Government spokesman Ali Rabiei was quoted by state media as saying the country had also produced 108 kg of uranium enriched to 20% purity, indicating quicker output than the rate required by the Iranian law that created the process.

Iran said in April it would begin enriching uranium to 60% purity, a move that would take the uranium much closer to the 90% suitable for a nuclear bomb.