Iraqi officials say the first day of early voting went smoothly in provincial elections that are seen as a key test of Iraq's stability.

Select groups of Iraqi voters were eligible to vote Wednesday, including about 615,000 soldiers, police and prisoners.

Election officials said voter turnout was high, but they did not immediately provide figures.

It is Iraq's first nationwide election since December 2005, when the country voted for a new parliament.

Fifteen million Iraqis are eligible to vote in the main election Saturday for councils in 14 of Iraq's 18 provinces. About 14,400 candidates are vying for 440 provincial council seats.

Iraqi Sunnis largely boycotted Iraq's last provincial elections in January 2005, handing Shi'ites and Kurds a disproportionate share of power. No such boycott is expected this time.

Iraqi authorities plan to tighten security for Saturday's vote by banning vehicles from the streets of major cities, closing airports and sealing Iraq's land borders.  Several candidates have escaped assassination attempts in recent days.  

Iraq's three autonomous Kurdish regions will hold provincial elections at a later date. Iraq's government delayed voting in a fourth province, Kirkuk, indefinitely after ethnic groups failed to agree on a power-sharing formula.

The provincial elections also represent a political test for Iraqi Prime Minister Nouri al-Maliki, who wants to boost the strength of his small Shi'ite faction ahead of parliamentary elections later this year.

In other news, Iraqi President Jalal Talabani met with Japan's former prime minister Shinzo Abe in Baghdad Wednesday in an effort to strengthen ties between the two nations.

Mr. Abe is visiting Iraq as a special envoy of Japanese Prime Minister Taro Aso.

While in Baghdad, officials signed a declaration of Japan-Iraq partnership.

Japan withdrew its air forces from Iraq at the end of 2008, ending a four-year mission there.