TEHRAN: Iran announced today the launch of work to produce 20 per cent enriched uranium, defying world powers which have warned of new sanctions unless Tehran halts its sensitive nuclear drive.

In Paris, a spokesman with US Defence Secretary Robert Gates who was winding up a visit said Washington is now aiming for a fresh United Nations sanctions resolution against the Islamic

republic in “a matter of weeks, not months.”

“From today we have started the 20 per cent enrichment in a separate cascade in Natanz,” Iran’s atomic chief Ali Akbar Salehi told the official IRNA news agency.

Several Iranian media networks reported the process was being

carried out under International Atomic Energy Agency supervision, as

the IAEA confirmed from its Vienna base that a team of its inspectors was in place to monitor.

Salehi said the separate cascade was “more on a lab scale,” adding it had 164 centrifuges — the

devices which rotate at

supersonic speed to enrich uranium.

“This can make between three to five kg of 20 per cent enriched uranium per month for the Tehran reactor,” he

said, referring to Iran’s internationally-supervised facility which produces medical isotopes.