Some papers are critical of Mr Koizumi's decision
Newspapers in Japan are divided over the government's decision to keep its troops in Iraq for another year.
Some come out strongly in support of the move, despite unease over the risks. Others criticise the decision and call for a clear exit strategy for the mission.
The Yomiuri Shimbun, Japan's largest-circulation daily, says withdrawal of the 550-strong non-combat mission from Iraq "is not an option" at what it calls a critical juncture in the country's reconstruction.
It says Japan needs to do its share as a member of the international community.
The paper acknowledges the security situation in Iraq is "bad", and it supports steps to ensure the safety of the Japanese troops stationed in Samawa, a Shi'ite city south-east of Baghdad.
The Sankei Shimbun sounds a similar note, calling the decision a "necessary course of action" despite the accompanying risks. It regrets that more troops are not being sent to reinforce the mission.
Exit strategy calls
But Mainichi Shimbun, a popular daily, accuses the government of trying to avoid a full parliamentary debate on the issue.
It says next year will be an important year for Iraq, but this means it will also be a more dangerous year for the Japanese troops stationed there. The paper urges the government to spell out a "concrete scenario" for withdrawal of the soldiers.
The Asahi Shimbun daily says Prime Minister Junichiro Koizumi faced an "agonising" choice, but that serious concerns remain over the extension of the mission.
The paper reiterates its view that the troops should be withdrawn next March, after Iraq's elections have taken place and to coincide with the withdrawal of the Dutch troops protecting the Japanese mission.
But it doubts that the government will pull the troops out even if they suffer casualties, since, in the paper's view, Mr Koizumi has consistently "bent over backwards" for the sake of relations with the US.
'Lack of independence'
The Tokyo Shimbun says Mr Koizumi now has an even greater responsibility to ensure the troops' safety, inasmuch as he made the decision to extend their mission despite the opposition of the majority of public opinion and for the sake of the Japan-US security alliance.
The paper's editorial urges the prime minister to be "decisive" should the situation call for the troops to suspend their mission and withdraw.
In the view of the Ryukyu Shimpo, the decision was not made with due consideration for the security situation in Iraq, the Iraqi people's wishes, or the stability of the Iraqi interim government.
It was made simply to "please" Washington, and the paper says this is a vivid manifestation of Japan's "lack of independence."
BBC Monitoring, based in Caversham in southern England, selects and translates information from radio, television, press, news agencies and the Internet from 150 countries in more than 70 languages.