IRAQ was transformed from a one-party dictatorship into a confusion of competing factions yesterday as ethnic, religious and tribal groups rushed to fill the vacuum left by the ousting of Saddam Hussein.

As American and British forces tried to impose order on the territory captured over the past three weeks, they were faced with the unenviable mission of running a deeply divided nation with no Iraqi leadership capable of assuming power in the near future.

Iraq’s political map used to be simple and one-dimensional: the Baath party.

Yesterday it included two Kurdish factions controlling the north; a pocket of Baathist control loyal to Saddam around his hometown, Tikrit; US military authority in Baghdad and a string of central and southern cities; Iraqi opposition forces in al-Nasiriyah; an unknown militia in the city of al-Amarah; British military rule in the south, with an unknown tribal sheikh promoted to Mayor of Basra; and the new US civil administration established in the southern-most port city of Umm Qasr.

To further complicate matters, exiled leaders and other groups, some of them supported by foreign governments, are planning to return in the coming days and weeks to stake their claim to post-Saddam Iraq.

Even the main coalition partners, the United States and Britain, are not agreed on the role of the United Nations and the composition of any future Iraqi leadership.

Senior Western diplomats gave warning yesterday that there was only a small window of opportunity to stabilise the country and establish a new Iraqi administration. They are clearly worried about a lawless hiatus undermining the military victory and are concerned about losing support in the Arab world. They also gave warning against expecting elections in Iraq any time soon.

The fate of the country will lie largely in the hands of retired US General Jay Garner, head of the Pentagon’s Organisation for Reconstruction and Humanitarian Assistance (Orha), the future civil administration of Iraq. Initially, his several hundred-strong force will lead relief efforts from their first base in Umm Qasr, under the command of the retired US General Buck Walters, who is charge of the southern third of Iraq.

“Umm Qasr is the first corner of Iraq that is totally free,” said General Walters, who likes to compare his team to the geriatric heroes of the comedy film Space Cowboys, who are brought out of retirement for one last mission.

The British also have a stake in the Orha operation, with half a dozen Foreign Office officials and army officers assigned to General Garner’s staff.

In the coming days General Garner is expected to move his operations from Kuwait to Baghdad and other Iraqi cities. After dealing with humanitarian issues, such as the supply of food and medicine, they will try to restart the machinery of government. They hope to complete their mission in a matter of months.

While the job of distributing aid and rebuilding the country will be a tough assignment, building a new democratic political infrastructure from scratch is the real challenge.

Despite their best efforts to wrap up the job as quickly as possible, American and British forces cannot control the political dynamic now under way in the country and the danger that Iraq could move from dictatorship to anarchy.

For example, tribal leaders, representing three quarters of the population, have emerged from the shadows to reclaim power. One unnamed tribal sheikh was installed by British forces as a de facto Mayor of Basra. A mysterious militia force this week seized control of the city of al-Amarah, before being ousted by US troops.

Yesterday Ahmad Chalabi, the Pentagon-backed leader of the Iraqi National Congress (INC), began to raise support on the ground in southern Iraq when he addressed thousands of people in the city of al-Nasiriyah.

“I salute all of you who have suffered so long under Saddam. I can tell you that those days are over,” Mr Chalabi, a former London-based banker, said. “No one has come here to rule over you. In the future Iraq will be ruled by you.”

After half a century in exile, he has swapped his business suit for combat fatigues and heads a force of 700 Iraqi opposition fighters working alongside US special forces. On Saturday other opposition leaders are expected to join him.

However, his move for power is being strongly resisted by the British and officials from the US State Department, who favour encouraging an indigenous leadership, even if it means dealing with former figures in Saddam’s military or ruling Baath party.

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