“Sex pictures,” he says, in his home 350 miles away. “They have been distributed to young children and to women by the soldiers of Britain.”

And this is only the start. “The female soldiers wear dresses which are very short,” the Ayatollah continues. “My assistants have come from Basra to tell me this.

“These things go against Islam and against what we believe. The Governments of Britain and the United States must prevent them at once.”

These, and more damaging rumours, are doing the rounds on streets of southern Iraq. In Karbala, where a multitude of Shia Muslims have gathered for the pilgrimage to the tomb of the Imam Hussein, there are tales of travellers robbed at American checkpoints.

“The soldiers take the dollars,” says one young man, who has heard it from the acquaintance of a friend. “And they leave them with the Iraqi money, which is worthless.”

There is no point in asking for evidence: the rumours are believed.

These are early days for the new Iraq, and it is still too early to speak of a backlash, but after the shock of liberation, the looting of the first days and the struggle to restore water and electricity, there are signs that many Iraqis are running out of patience with their liberators.

The message from every Iraqi to whom I have spoken was summarised by a thin young man carrying a huge red flag emblazoned with a Koranic slogan. “We thank Mr Bush and Mr Blair very much for saving us from Saddam,” he said in front of the shrine. “But now we want Mr Bush and Mr Blair to get out.”

Karbala is a good testing ground for public opinion, for few cities in Iraq have more reason to be grateful to the coalition forces. In Basra and al-Nasiriyah, British and US Marines operate checkpoints and patrol the streets, but in their anxiety to avoid upsetting sensibilities in the holiest city of the Shia faith, in Karbala they have behaved with exemplary restraint.

The Iraqi forces gave up here without much of a fight and there was less bombing and looting than elsewhere. The pilgrimage has been almost incident-free.

But gratitude for the liberation has not translated into affection for the liberators. “Yes, yes, to Islam!” goes one of the favourite pilrimage chants. “No America! No Saddam!” The stories of seductively dressed female soldiers and the corruption of youth with smutty pictures are parodies, and many Iraqis know it, but there is a collective will to believe in smears that speaks of a deep dissatisfaction with Iraq’s occupied status.

“They had a goal when they came here, to get rid of Saddam,” Fatima Hassam, who walked to Karbala for two days with her mother and daughter, said. “But we cannot live under an occupation.”

Another pilgrim, Hassan Mohammed, said: “If Britain and America fail to understand this about the Iraqi people, then we will fight them. We will fight them with whatever we have. We will fight them with the wood from the trees.”

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