ONLY a few miles separate the rebel city of Fallujah from the sprawling complex of US Marine bases. While the Iraqi city is steadily emptying of people, the American camps are rapidly filling up with extra men and armour, ready for what is expected to be a fight for the very soul of Iraq.

Almost as soon as the United States elections are over, the 1st Marine Expeditionary Force, reinforced by army units specially drafted in from across Iraq, is expected to mount a massive attack on Fallujah.

Skirmishes have begun already. Every day F18 fighter-bombers screech up from carriers in the Persian Gulf to bomb suspected guerrilla safehouses or mortar positions. Eight Marines were killed when a suicide car bomber rammed their convoy at the weekend. And from the military camps, the boom of outgoing mortar shells or the occasional thump of an incoming round regularly breaks the silence of the autumnal desert. In chow halls, Iraqi National Guards soldiers share hi-carb meals with Marines in training for the showdown.

Few doubt that an attack is imminent after Iyad Allawi, the interim Iraqi Prime Minister, gave warning on Sunday that his patience was wearing thin and that the stop-start talks to defuse the crisis were in their “final phase”. Guerrilla sources told The Times that Mr Allawi had given up on talks weeks ago, storming into negotiations and telling the rebels’ representatives: “It is too late, the train of war is already in Fallujah.”

Publicly Mr Allawi has called on the people of Fallujah to hand over Abu Musab al- Zarqawi, the terrorist mastermind who has kidnapped and bombed his way to a $25 million (£14 million) bounty, matched only by the price on the head of Osama bin Laden. The city elders have replied that even the Americans have been unable to stop al-Zarqawi and his powerful network. They cannot be expected to step in where the superpower has failed.

In anticipation of the battle, and with memories of April’s bloody and abortive invasion still fresh, as many as two thirds of Fallujah’s 280,000 residents have fled, leaving a ghost town where American commanders expect to confront up to 5,000 rebels and foreign fighters. Regular airstrikes have left many of the buildings, including Fallujah’s renowned kebab shop, as nothing more than piles of dust.

“Whoever looks around Fallujah now can only feel sadness. The damage is so heavy the suburbs look like they were hit by an earthquake,” Mohammed al-Alwani, a bank employee, said.

The Iraqi fighters are a mixture of Islamic extremists, Saddam Hussein loyalists, fiercely territorial tribesmen and criminal gangs, according to Marine intelligence officers. Their allegiances, goals and tactics are constantly shifting: the increase in brutal attacks on Iraqis by the foreign Islamists are showing signs of straining relations between those cells and the Iraqi resistance.

Both sides have had months to prepare for battle. The Marines invaded in April after four American security contractors were burnt, mutilated and hung from a bridge. In the face of the toughest combat since the Vietnam War, with casualties rising on both sides, US commander ordered a halt to its three-week offensive and the creation of a local militia to enforce law and order.

But the Fallujah Brigades were an abject failure, siding with the guerrillas and, in many cases, handing over their weapons to them. Fallujah became a staging point for guerrillas heading across the western and northern areas of the country, pushing a wedge of insurgency through western Baghdad and to the heart of the capital.

With Iraqi elections looming in January, the interim Government has decided that it has to regain control of the rebellious Sunni Triangle or risk seeing the entire US-backed democratic project in Iraq crumble.

“We are gearing up to do an operation and when we’re told to go, we’ll go, and we’ll whack them,” Brigadier-General Dennis Hajlik, the Marines’ deputy commander, said. “As for the number of troops, it’ll be enough to get the job done in a decisive fashion.”

Iraqi forces will be involved in the operation to give it an “Iraqi face”, he said. The Iraqi troops have been in intensive training since the April uprising, when up to 80 per cent of those fighting in Fallujah melted away.

However, the guerrillas have also had months to prepare for the onslaught. Resistance groups say that they have been moving more weapons along the rat-runs through the southwestern desert from Saudi Arabia and along the River Euphrates from Syria. The Black Watch have been deployed to the south of Fallujah to stop more weapons and men heading in or out once the battle starts.

Among the US Marines morale is high, but many admit to understandable pre-battle jitters. “It is a scary thought,” said Cameron Begbie, a 23-year-old Marines medic from Fresno, California, who arrived here a month ago and has never seen combat.

But he knows what he is fighting for and is determined to see the job through. “It’s a city that needs to be liberated to ensure elections go down in the rest of the country. You can’t have a free country when you have pockets of resistance,” he said, adding that few of his comrades believed that the fight would be a quick one.

One of the key tests will be what happens to Fallujah after the battle. Upriver along the Euphrates, US forces have never left Ramadi, but the provincial capital is a virtual battlefield, where gunfights erupt almost daily. The Marines will have to install an effective Iraqi force in the volatile tribal cities to quell violence and allow reconstruction to start and the economy to revive.

Until then the Marines are writing letters home and trying to concentrate on the fight ahead. “I spend as much time as I can with my guys, let them know: ‘I’m with you, you’re with me’,” Corpsman Begbie said. “We’re all nervous, we all want to get back to our families safe and sound.”

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