IRAQ - Tehran Defiance.

Tehran defiantly rejects US accusations that it has supplied armour-piercing explosives used to kill American troops in Iraq. President Mahmoud Ahmadi-Nejad on Feb. 12 told ABC television Washington was trying to find "excuses" to prolong the US presence in Iraq, adding: "There should be no foreigners there in Iraq - and then you will see that you have peace in Iraq. There should be a court to...verify the case. The position of our government...is also the same - we are opposed to any kind of conflict in Iraq".

Ahmadi-Nejad was responding to claims from a senior US defence official in Baghdad who on Feb. 11 said armour-penetrating explosives which had killed 170 "coalition forces" were of Iranian manufacture. A second US official said the US assessment was that the supply and training of Iraqi insurgents by Tehran was decided by the "highest levels of the Iranian government".

Iranian Foreign Ministry spokesman Mohammad-Ali Hosseini said the US had a "long history in fabricating evidence" and that the charges were "unacceptable". He added that Iran opposed "any intervention in Iraq's internal affairs...[and] a weakening of the popular Iraqi government".

American officials have long suggested that Iran was involved in supporting violence in Iraq, but the Feb. 11 announcement, supported by the presentation of bomb fragments, came after a stepping-up of US rhetoric against Iran and the dispatch of a second aircraft carrier, the John G Stennis, to the waters off southern Iran. The UNSC deadline for Iran to suspend most of its nuclear programme runs out on Feb. 21. Hosseini on Feb. 12 reiterated that Iran was ready for negotiations, even over the suspension of uranium enrichment.

Officials in Tehran critical of Ahmadi-Nejad suspect the US allegations over Iran's role in Iraq are designed to thwart any possibility of compromise. The FT on Feb. 13 quoted a "senior reformist" in Tehran as saying: "everything in the region...[was] now overshadowed by US-Iran tensions. The wise men must increase their efforts. I was alarmed when I heard the US accusations on the television - they were very direct. My fear is that this is all part of preparation for at least keeping open the real option of attacks on Iran".

The EFP - the device which US officials say is evidence of Iranian support for Iraqi militants - is one of the most feared weapons for US forces in Iraq. It is a device US soldiers say is exclusively associated with Shi'ite militias. This is a refinement of the shaped charge technology which has been used to destroy tanks and other military vehicles since the World War II. US officials said the weapons found in Iraq created a deadly slug of molten metal which could tear through armour. They said the signature part of the weapon linking it with Iran was the machining process.

Speaking at a news conference in the East Room of the White House on Feb. 14, President Bush dismissed as "preposterous" the contention that the US was drawing unwarranted conclusions about Iran's role in Iraq. He endorsed assertions until then presented only by anonymous military and intelligence officials, who had said an elite branch of Iran's Islamic Revolutionary Guard Corps (IRGC) known as the Quds Force had provided Shi'ite militias in Iraq with EFPs. "I can say with certainty that the Quds Force, a part of the Iranian government, has provided these sophisticated IED's that have harmed our troops", Bush said, using the abbreviation for improvised explosive devices. "And I'd like to repeat, I do not know whether or not the Quds Force was ordered from the top echelons of the government. But my point is, what's worse, them ordering it and it happening, or them not ordering it and its happening?"

Asked about a possible US response to Iranian interference, Bush said: "We will continue to protect our troops". (The Quds Force has historically reported to Iran's top theocrats). As Bush discussed Iran in Washington, the top US military spokesman in Baghdad, Maj. Gen. William Caldwell, provided a more detailed, on-the-record account of how the US believed the IEDs, particularly the EFPs, got to Iraq. Caldwell was careful not to link the actions of Quds directly to Iran's top leaders. He said US assertions about a link between the weapons and the force were based on information obtained from people, including Iranians, detained in Iraq "in the past 60 days", adding: "They in fact have told us that the Quds Force provides support to extremist groups here in Iraq in the forms of both money and weaponry. They have talked about how there are extremist elements that are given this material in Iran and then it is smuggled into Iraq. We have in fact stopped some at the border and discovered it there, coming from Iran into Iraq".

Bush suggested that it did not matter whether senior Iranian leaders were involved, saying: "What matters is...that we're responding". He said if the US found either networks or individuals "who are moving these devices into Iraq, we will deal with them". Gary Sick, an expert on Iran at Columbia University, said there was a "danger of accidental war". He said: "If anything goes wrong, if something happens, there's an unexplained explosion and we kidnap an Iranian, and the Iranians respond to that somehow, this could get out of control".

Bush has refused to meet with Iran's leaders, and on Feb. 14 said he did not believe it would be an effective way of persuading the Iranians to give up their nuclear goals. He said: "This is a world in which people say, 'Meet! Sit down and meet!' And my answer is, if it yields results, that's what I'm interested in".