UN pulls out its mission as Iran nuclear stand-off hits critical phase

The setback is likely to increase the risk of a confrontation with the West over Iran’s nuclear ambitions.

However, Iran’s supreme leader, Ayatollah Ali Khamenei remained defiant, saying Iran’s nuclear plans would remain unchanged despite mounting international pressure.

He told state TV: “With God’s help, and without paying attention to propaganda, Iran’s nuclear course should continue firmly and seriously. Pressures, sanctions and assassinations will bear no fruit. No obstacles can stop Iran’s nuclear work.”

A team from the Vienna-based International Atomic Energy Agency (IAEA) had hoped to inspect a site at Parchin, south-east of Tehran, where the agency believes there is a facility to test the kind of explosive charges necessary to detonate a nuclear warhead.

“During both the first and second round of discussions, the agency team requested access to the military site at Parchin. Iran did not grant permission for this visit to take place,” the IAEA said.

“It is disappointing that Iran did not accept our request to visit Parchin. We engaged in a constructive spirit, but no agreement was reached,” said IAEA director general Yukiya Amano.

As sanctions mount, ordinary Iranians are suffering from the effects of soaring prices and a collapsing currency. Several Iranian nuclear scientists have been killed over the past two years in bomb attacks that Tehran has blamed on arch-adversary Israel.

In response, Iran has issued statements asserting its right to self-defence and threatening to block the Strait of Hormuz, a vital oil tanker route in the Gulf.

The collapse of the nuclear talks came as Iran seems increasingly isolated, with some experts seeing the Islamic republic’s defiance as evidence that it is in no mood to compromise.

Elections on 2 March are expected to be won by supporters of Mr Khamenei, an implacable enemy of the West.

The failure of the two-day visit by the IAEA could now hamper any resumption of wider nuclear negotiations between Iran and six world powers – the United States, China, Russia, Britain, France and Germany – as the sense grows that Tehran feels it is being backed into a corner.

Some analysts believe the Iranians may be trying to keep their opponents guessing.

“But they may be overdoing the smoke and mirrors and, as a result, leaving themselves more vulnerable,” said Professor Rosemary Hollis of City University London.

Iranian analyst Mohammad Marandi said: “Under the current conditions it is not in Iran’s interest to co-operate more than is necessary because the West is waging a war against the Iranian nation.” .

An IAEA report in November found Iran had built a large containment chamber at Parchin to conduct high-explosives tests. The UN agency said there were “strong indicators of possible weapon development”.