Iran is secretly forging ties with al-Qaida elements and Sunni Arab militias in Iraq in preparation for a summer showdown with coalition forces intended to tip a wavering US Congress into voting for full military withdrawal, US officials say.

"Iran is fighting a proxy war in Iraq and it's a very dangerous course for them to be following. They are already committing daily acts of war against US and British forces," a senior US official in Baghdad warned. "They [Iran] are behind a lot of high-profile attacks meant to undermine US will and British will, such as the rocket attacks on Basra palace and the Green Zone [in Baghdad]. The attacks are directed by the Revolutionary Guard who are connected right to the top [of the Iranian government]."
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US officials now say they have firm evidence that Tehran has switched tack as it senses a chance of victory in Iraq. In a parallel development, they say they also have proof that Iran has reversed its previous policy in Afghanistan and is now supporting and supplying the Taliban's campaign against US, British and other Nato forces.

Iran's secret plan for summer offensive