Iran has slowed the expansion of its uranium enrichment programme, the head of the International Atomic Energy Agency (IAEA) said yesterday, after Western powers threatened to hit Tehran with harsher sanctions. The Iranian shift was detected by IAEA inspectors last week after months in which Iran accelerated the installation of centrifuge machines that refine uranium.

The US has said it, Britain, France, Germany, Russia and China have begun deliberating a third and more painful batch of UN sanctions.

IAEA director Mohamed ElBaradei said agency inspectors who just revisited Iran's vast underground enrichment plant at Natanz also noticed a "fairly slow" pace of feeding uranium into the centrifuges for enrichment.

The US voiced scepticism over the slowdown. "I would not necessarily read too much into that and whether or not that is a conscious political decision or whether or not it's an issue of technical problems," State Department spokesman Sean McCormack said.

PHOTO CAPTION

Iranian ambassador to the International Atomic Energy Agency Ali Asghar Soltanieh attends a meeting at the IAEA headquarters in Vienna, 2006. (AFP)