Plans are on track to take Iraq's first complete census in 23 years, a process that will help answer questions critical to the future of Iraq's northern oilfields, such as 'how many Kurds live in Kirkuk?'

The long-delayed count, which may shut down the country for two days in October, is also expected to determine how many Iraqis live abroad and how many have been forced to move within Iraq in seven years of war, census chief Mehdi al-Alak said.

The census was postponed for a year over worries it was being politicised. Ethnic groups in contested areas like the northern city of Kirkuk, home to Arabs, Kurds, Turkmen and a valuable part of Iraq's oil fields, opposed it because it might reveal demographics that would undermine political ambitions.

The count could provide answers or create more squabbles in a diverse nation riven by sectarian violence following the US invasion in 2003 and now trying to bolster fragile security gains while deciding how to share out its vast oil wealth. Iraq has the world's 3rd largest crude oil reserves.

The autonomous Kurdish region in the north claims Kirkuk as its own. The census will determine whether Kurds are the biggest ethnic bloc in the city, which could bolster that claim.

It will also find out how many people live in Iraqi Kurdistan, which will define its slice of central government revenues, currently 17 per cent.

If the census finds Kurds are a greater percentage of the total population, the constitution says the region gets more money, and retroactive payments.

What it won't do, Alak said, is attempt to determine which of the hotly disputed areas belong to whom.

'It is not our business to decide their destiny,' Alak, the head of the Central Organisation for Statistics and Information Technology (Cosit), said in an interview this week. 'We count the people in the province where they live. Deciding the destiny of the areas is the business of the politicians.'

The census will be the first to include the Kurdish region since 1987. A 1997 census counted 19 million Iraqis and officials estimated there were another 3 million in the Kurdish north.

The current national population is believed to be 'not less than 30 million,' Alak said.

'We started three months ago the listing and mapping process that is the backbone of our work,' he said. 'We have initial numbers of houses, buildings, families, and individuals.'

The census will show the religious makeup of a predominantly Muslim nation but will deliberately not ask a resident's sect.

Sectarian fighting has killed tens of thousands since Saddam Hussein's minority Sunni-led regime was deposed and majority Shi'ites gained political power.

'He or she would say Muslim, Christian, Sabian, Yazidi, but the form doesn't contain sect questions like Sunni or Shi'ite,' Alak said. 'It is very sensitive now because of our circumstances. (To ask this question) is not recommended.'

Between 200,000 and 250,000 schoolteachers will be trained this summer and mustered in the last week of October to carry out the count. The exact date has not been set.

The teachers will be joined by 10,000 to 15,000 other government workers, as well as security forces to protect them in restive areas like Nineveh province, where remnants of al Qaeda are still in evidence.

All Iraqis will be ordered to stay home for one and possibly two days, a census tradition in Iraq, Alak said. Enumerators will go to each of the estimated 5 million households to count heads, examine identification, ask about education and profession and register rates of births and deaths.

Alak said Iraq's total population should be known about 15 days after census day, but more specific demographics will take about 10 months to tally.-Reuters