U.N. officials have said they agree in principle with a senior Iraqi Shi'ite religious leader about having elections in the country. But they say any election must be well prepared.

The U.N. fact-finding team made the comments after a rare meeting with Iraq's leading Shi'ite religious leader in the holy city of Najaf. The U.N. special representative to Iraq, Lakhdar Brahimi, said he agreed with Ayatollah Ali al-Sistani that the polls should happen as soon as possible, but he said they should be well prepared.

Ayatollah al-Sistani is Iraq's most revered Shi'ite cleric and he opposes U.S. plans to hold elections next year, after handing over power this June to an interim authority picked in regional meetings. The United States says there is not enough time to organize general elections in Iraq by the planned handover date. But the Ayatollah disagrees.

Tens of thousands of Shiites took to the streets in protest last month after Ayatollah al-Sistani encouraged them to oppose the U.S. plan.

Any election will be a complicated logistical operation, involving developing voter lists, arranging for ballots and secure counting facilities and many other types of preparation. But the continuing insurgency could pose the greatest obstacle to holding free and fair elections.

Security concerns have been heightened by two deadly car bombings in Iraq this week - one south of Baghdad on Tuesday and another in the capital on Wednesday. More than 100 people died in the attacks.

Earlier in the week, the head of a Shi'ite Muslim political party, Abdul Aziz al-Hakim, gave Mr. Brahimi a report claiming that early elections are possible. Shi'ites make up about 60 percent of Iraq's population.

The U.N. team arrived during the weekend and is operating under tight security. It is the first U.N. mission to operate in Iraq since last August, when a car bomb at U.N. headquarters in Baghdad killed more than 20 people, including the special representative.

The U.N. team includes election experts and security officials. They will reportedly spend a total of 10 days in Iraq. Their conclusions, which are non-binding, are expected to be announced at U.N. headquarters in New York next week.