Tensions rise as Washington accuses Iran over militias

Tensions between the US and Iran were set to escalate last night after it was revealed that President George Bush had signed an executive order several months ago, authorising American troops to undertake wide-ranging military action against Iranian operatives active inside Iraq.

That discreetly issued directive was the basis for at least two raids against Iranian targets last week - including one in the Kurdish city of Irbil.

The President's decision - revealed by Condoleezza Rice, the Secretary of State, who yesterday arrived in the Middle East for talks with Israeli and Palestinian leaders - was taken amid growing concern that Iran has been providing weapons and training to Shia forces in Iraq. Without irony, the US has long accused Iran of meddling in the affairs of its neighbour.

"There has been a decision to go after these networks," Ms Rice told The New York Times before leaving Washington. "[The President acted] after a period of time in which we saw increasing activity among Iranians in Iraq and increasing lethality in what they were producing." Her comments echoed those made by Mr Bush during his address to the nation on Wednesday evening, when he outlined his plan to send an additional 20,000 troops to Iraq. In his address, without citing any evidence, he accused Iran of supplying support for attacks being carried out on US troops and vowed to respond.

"[Iran and Syria] are allowing terrorists and insurgents to use their territory to move in and out of Iraq. Iran is providing material support for attacks on American troops," Mr Bush said. "We will disrupt the attacks on our forces. We will interrupt the flow of support from Iran and Syria. And we will seek out and destroy the networks providing advanced weaponry and training to our enemies in Iraq."

Privately, US officials claim Iran has provided explosives and infrared triggering devices for roadside bombs that can penetrate armour. Some of the attacks have been on British forces in southern Iraq. Officials have also reportedly claimed that thousands of Shia militia fighters have been trained in Iran by the Iranian Revolutionary Guards and the Ministry of Intelligence and Security. Again, no evidence to support these claims has been made public.

US officials deny that the Bush administration is seeking to provoke Iran. The White House spokesman, Tony Snow, said that there was "an urban legend that's going around that Mr Bush was trying to prepare the way for war" with Iran or Syria.

But in recent days the US has deployed an additional aircraft carrier off the Iranian coast. USS John Stennis will join the battle group led by USS Dwight D Eisenhower. In addition, a 600-strong Patriot anti-missile defence system unit from Fort Bliss, Texas, has been deployed to the Middle East, though it is unclear where precisely it will be located.

Against this backdrop, Ms Rice, perhaps not surprisingly, has played down expectations from her trip to the Middle East - her eighth since becoming Secretary of State. Speaking to reporters on the way to Israel, she said: "I'm not coming with a proposal. I'm not coming with a plan." She added: "I expect this trip to really be one in which we have intensive consultations. If you don't lay the groundwork very well, then it's not going to succeed. And I think no plan can be made in America."

Her mission was given some headway last night by news that significant progress had been made in secret coalition talks in Damascus between the supreme Hamas leader and envoys of the Palestinian president, Mahmoud Abbas. As another round of talks was held yesterday in the Syrian capital, officials from both sides signalled a sudden shift in atmosphere after several weeks of tough internal fighting.

Ms Rice was last night due to meet Israel's defence and foreign ministers. Today she heads for the West Bank city of Ramallah to meet Mr Abbas, and tomorrow talks are scheduled with the Israeli Prime Minister, Ehud Olmert. Her trip also includes stops in Jordan, Egypt, Saudi Arabia, Kuwait, Germany and Britain.