HUNDREDS of tonnes of high explosives that could be used to detonate nuclear weapons have vanished in Iraq since the United States and Britain invaded, the International Atomic Energy Agency (IAEA) said yesterday.

The United Nations nuclear watchdog said that 350 tonnes of powerful explosives, known as HMX and RDX and which could be used to manufacture terrorist bombs, had disappeared from al-Qaqaa military facility just south of Baghdad.

The announcement, and the heightened risk that the invasion could have led to the proliferation of the very weapons that it aimed to curb, came at the worst possible time for President Bush, just seven days before the American presidential election.

John Kerry, Mr Bush’s Democratic challenger, pounced on the announcement. At a rally in New Hampshire, he said that Mr Bush had committed “one of the greatest blunders” of his Administration in failing to secure the explosives.

“George W. Bush who talks tough — talks tough — and brags about making America safer, has once again failed to deliver,” Mr Kerry said.

“After being warned about the danger of major stockpiles of explosives in Iraq, this President failed to guard those stockpiles.”

Mr Kerry added that terrorists could use the material “to kill our troops, our people, blow up airplanes and level buildings”. He added: “This is one of the great blunders of Iraq, one of the greatest blunders of this Administration, and the incredible incompetence of this President and this Administration has put our troops at risk and this country at greater risk.”

Scott McClellan, one of Mr Bush’s senior spokesmen, played down the threat. He said that the Administration’s first concern was whether the weapons missing from al-Qaqaa posed a nuclear proliferation threat, and they did not.

“We have destroyed more than 243,000 munitions,” he said. “We’ve secured another nearly 163,000 that will be destroyed.”

In the early days after it took Baghdad last year, the US-led coalition was criticised for allowing looting on a massive scale that stripped bare government buildings, including sensitive military facilities. The disappearance came just weeks after the IAEA said that precision machinery that could be used to make nuclear weapons had also vanished.

Although the explosives were categorised as conventional weapons, the IAEA supervised them as they could also be used to detonate a nuclear warhead.

The loss of the explosives was revealed in a report by the US-installed Iraqi interim Government to the IAEA, which still imposes an accounting of all sensitive materials in Iraq twice every year.

The report, by Rashad Omar, the Iraqi Minister of Science and Technology, added that Condoleezza Rice, the American National Security Adviser, had been informed of the development in the past month.

The IAEA had been keeping track of the explosives during weapons inspections before the war, but had been blocked from returning by the US, which set up its own team, the Iraq Survey Group, to trace Saddam Hussein’s weapons of mass destruction. While most of the roadside bombs and explosives-packed cars that have been used by the insurgents in Iraq are improvised out of looted artillery shells, mortar rounds and landmines, some suicide bombers have used high-grade explosives of the type that have gone astray.

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