Iran has developed technology to separate uranium from its ore, reinforcing the Islamic republic's self-sufficiency in the nuclear fuel cycle, state television has reported.

The technology, known as a mixer-settler, is used to separate the uranium from the mined ore to produce concentrated uranium oxide - also known as yellowcake - which can then be converted and enriched in nuclear fuel work.

"The mixer-settler can be used effectively in the fuel cycle for producing zirconium and uranium," one of the engineers, who helped develop the machinery, said on television.

"It minimises the use of solvent and has a recycling mechanism," he said, adding the country could not afford to buy the machinery before. Zirconium is a metal used for coating tubes in nuclear plants to prevent corrosion.

In a mixer-settler, two liquids of different density are mixed, allowing certain chemical compounds to pass from one liquid phase into the other. The two liquids then settle due to natural gravity.

The United States accuses Iran of trying to master the civil nuclear fuel cycle as a cover for a military programme to obtain atomic weapons - a charge Tehran vehemently denies.

Stumbling block

Iran announced in 2003 its intention to start extraction of uranium from a mine at Saghand, in the province of Yazd, which has an estimated 1.5 million tonnes of uranium ore.

Once refined, the yellowcake is usually sent to a facility for conversion into uranium hexafluoride gas and subsequently for enrichment before making it to a nuclear reactor.

In a highly enriched form, uranium can be used in the core of an atomic bomb.

In August, Iran ended its freeze on the conversion of yellowcake to uranium hexafluoride gas (UF6) at a facility near the central city of Isfahan. So far, it has agreed to maintain a freeze of enrichment at a plant in Natanz.

Iran's right to enrichment has proved a major stumbling block in talks with the European Union on its nuclear programme.

PHOTO CAPTION

Two Iranians work at the zirconium production plant, part of the nuclear facilities in Isfahan. (AFP)