Iraqi authorities will ask the United Nations to oversee a national census if and when it returns to Iraq, in what could be a politically charged move ahead of elections due next year.
If the survey is conducted, it would be the first full accounting of the country's make-up in more than 45 years.
Depending on what questions are asked, it could be an explosive move in a country where there are few accurate figures on the size of the population or its religious and ethnic breakdown, both of which are deeply divisive issues.
Adnan Pachachi, president of the Iraqi Governing Council, told a pro-democracy gathering in Baghdad a census was one of several issues that needed to be addressed before US authorities hand power back to Iraqis on July 1.
"We will ask the United Nations to run a complete, exact census and to put in place voter lists via voter registration centres throughout Iraq," Pachachi told around 250 Baghdad leaders gathered to discuss the power transfer.
It is not yet clear whether the United Nations will return to Iraq after pulling out of the country in October last year following the bombing of its Baghdad headquarters.
US authorities and the Governing Council have asked it to return to help decide whether it is possible to hold early, direct elections before the July power transfer, as Iraq's leading Shia cleric, Ayatollah Ali al-Sistani, has demanded.
Currently, the US-led administration plans to hold a series of indirect caucuses leading to creation of a transitional authority that would take power from July. A constitution would then be written and elections held in 2005.
UN Secretary General Kofi Annan this week sent a small security team to Iraq to weigh the risks of a UN electoral delegation visiting the country. Depending on what the team reports, the specialist group will be sent to assess whether direct, national elections can be held.
US-led authorities in Iraq have resisted calls for direct elections, saying there is not enough time to organise free and fair polls before the power hand-over and there are no electoral rolls or voter registration data.
Pachachi's call for a census is likely to dismay US administrators who have avoided discussing the issue, fearing it could be too incendiary in a country still dealing with its recent history, let alone its sectarian and ethnic differences.
The last accepted, official census was held in 1957. The former Baath party regime conducted censuses in 1977, 1987 and 1997, but these are widely regarded as inaccurate.
Iraq's population is estimated to number 25 million, around 60 percent of whom are Shia Muslims. Sunni Muslims make up slightly over 35 percent, and the remainder are Christians and from other smaller sects.
As well as the sectarian divisions there are ethnic divides, with around 70 percent of the population Arab, about 20 percent Kurd and most of the remainder Turkish-speaking Turkmens.