An Iraqi police officer says U.S. troops have mistakenly shot and killed three Iraqi policemen and wounded two others outside the northern city of Kirkuk.

The officer says American troops opened fire, apparently believing the men were bandits. The incident is said to have taken place at about midnight Friday at a checkpoint on the road connecting Kirkuk and the capital, Baghdad.

The U.S. military has yet to comment on the incident.

In southern Iraq, Spanish Prime Minister Jose Maria Aznar has made a surprise visit to his country's troops. Mr. Aznar arrived in the southern town of Diwaniya late Friday and was scheduled to leave later Saturday.

Spain has actively backed the U.S.-led operation in Iraq and has 1,300 soldiers serving there. Ten Spaniards have lost their lives. In the worst attack late last month, insurgents ambushed and killed seven Spanish intelligence agents.

In another development, U.S. officials say they welcome a call by U.N. Secretary-General Kofi Annan for talks with the Iraqi Governing Council and the U.S.-led coalition about the organization's future role in the country.

A U.S. State Department spokesman said Friday such talks would be useful, but that the Bush administration is not yet ready to endorse a specific date. Mr. Annan called for a meeting January 15.

The spokesman also said Secretary of State Colin Powell discussed the issue by telephone with Mr. Annan on Friday.

U.N. staff pulled out of Iraq in October after a series of attacks, including a suicide truck bombing at the U.N. office in Baghdad that killed 22 people. U.S. officials regretted the move and said they would welcome a meeting to facilitate the U.N.'s return to active involvement in Iraq.