In a relatively short period, the security conditions and atmosphere in Basra have changed dramatically.

The reason for the transformation was predicted by General Sir Richard Dannatt, the head of the Army, in October last year when he gave his warning that British troops in Iraq were becoming more of a problem than a solution. In other words, their very presence was sparking the eruption of violence in southern Iraq because they were the principal targets for the extremists.

Once the last remaining 500 soldiers based in Basra city at the Basra Palace had withdrawn - early last month - the level of violence began to fall. Today, the difference is tangible. British troops no longer patrol in Basra, that role is now left to the Iraqi security forces, but they still transit through the city en route to the Shatt al-Arab waterway. Yet apart from the odd small arms fire, none of the troops so far have been attacked.

With all the troops now based at the Basra air station a few miles northwest of the city, they are no longer viewed as a provocative occupying force.

However, the reason for the sudden drop in violence in southern Iraq had more to do with Basra politics than military strategy.

The key to the change in atmosphere which led directly to Gordon Brown’s decision to cut troop numbers by half to 2,500 next spring followed a secret deal reached between a new Iraqi army commander and Shia militia leaders in Basra, senior British military officers told The Times.

General Mohan al-Firaiji, a four-star commander newly appointed by the Government in Baghdad to take charge of security in Basra, along with General Jalil Khalaf, a new police chief in the southern city, persuaded the Shia militia groups “to leave the British alone”. In return, the 500 British troops at Basra Palace would withdraw.

The 500 soldiers withdrew without incident in early September once a suitable Iraqi army unit had been earmarked to take over the Basra Palace base. The British sources said that without the deal with the Shia militia for a quid pro quo arrangement, the withdrawal could have been a bloody affair. Many experts had warned that the pullout would lead to heightened violence and to British casualties. The opposite has been the case.

The role played by these two senior Iraqi figures had such a significant impact on security conditions in Basra - violence has been reduced beyond expectations - that British commanders are now freely admitting that the circumstances have changed out of all recognition.

The reason why the Shia militia agreed to the secret deal was that General Mohan and General Jalil had both been appointed by Baghdad. It demonstrated to the Shia power-brokers in Basra that the government was determined to play a dominant part in the politics of southern Iraq, something the leaders in Baghdad had failed to demonstrate hitherto.

It needed two strong men from out of the Basra area to bash heads together in Basra and to persuade the rival and feuding Shia militia to stop killing each other and to leave the British troops alone. So far it has worked spectacularly well, although the rocket attack on the British airbase camp outside Basra on Monday evening was evidence that not all the Shia groups are happy with the Mohan deal.

For the British, the ceasefire and the withdrawal of all the troops to the single base at the airport, dramatically reducing Britain’s military footprint in southern Iraq, has transformed the operation from a largely kinetic mission - one round after another of brutal confrontations with “the enemy” - to a supportive role, guiding and training the Iraqi forces and offering help if required, although, so far, General Mohan and his men have coped more than adequately.

”We’re as busy as ever, but the difference is that we’re no longer being hit every day and we’re not being rocketed as much in camp, and none of us minds that,” said Major Mark Wilson, officer commanding A Company 4 The Rifles, whose men suffered months of attacks when they were based at Basra Palace, prior to the withdrawal, with five of the battalion killed. “This really has been a tour of two halves,” he said.

One fear remains. If all the British troops leave Iraq within the next 12 to 14 months, is there a danger that the Iraqi solution to the challenges, aided and abetted by influence from Iran, might lead to a Talibanisation of Basra city, with the extremists forcing every woman to wear a veil and every man to grow a beard?

The most senior British military here remain optimistic that down south, and elsewhere in Iraq, the instinct of the Iraqi people will be to remain a secular, though religious, community.

One senior British military source said there were concerns that “Islamification” had begun to take hold in Muthanna province when the British handed over security control to the Iraqis a few months ago, but the fears proved groundless. There has been no imposition of Sharia law in Muthanna.

In Basra, there have been cases of women being attacked for not wearing the veil. But the Iraqi police chief has vowed to protect the women of Basra, and the British military are convinced the city will also resist any move towards Talibanisation; and that despite the much mooted fear of an Iranian take-over of southern Iraq, the people themselves have shown no enthusiasm for embracing Iran. “They suffered for decades under Saddam Hussein and have no desire to let Tehran dictate their lives,” one senior officer said.

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