UN nuclear watchdog confirms Iran's advanced centrifuges installation

"The centrifuge machines, as they are engaged in research and development, will help with increasing the stockpile," spokesman Behrouz Kamalvandi said.

"The capacity of these machines is many times more than the previous machines. This started as of yesterday (Friday)," he told reporters.

But Kamalvandi said Iran would allow the UN atomic agency - the International Atomic Energy Agency (IAEA) - to continue monitoring its nuclear programme, as it has done under the 2015 accord with major powers.

Iran and three European countries - Britain, France and Germany - have been engaged in talks to save a 2015 nuclear deal that has been unravelling since the US withdrew from it in May last year.

European powers have emphasised their reliance on the IAEA in monitoring Iran's nuclear activity, however some concerns have been raised over possible hindrances to the agency's work.

In a report published on August 30, the IAEA said in an apparent hint at worries about access that "ongoing interactions ... require full and timely cooperation by Iran".

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