Four US soldiers were wounded and their Iraqi translator was killed today when gunmen ambushed their convoy south of Baghdad.
Bombings and shootings have killed 378 US troops since the US-led war that toppled Saddam Hussein began in March.
The United States wants the NATO to take command of a force controlling a swathe of south-central Iraq, currently lead byPoland, to take off some heat from its forces.
But General Harald Kujat, chairman of NATO's military committee, told the
Berliner Zeitungnewspaper today it would take time to plan any mission in Iraq even if leaders of the 19-nation alliance gave the go ahead at a summit in June for such an operation.
Violence in Iraq is set against fears that simmering sectarian and ethnic tensions could erupt into a conflict.
Abdel Aziz al-Hakim, who has led Iraq's main Shi'ite Muslim political group since his brother's assassination last year, said he believed al-Qaeda played a role in his brother's death.
He said he had "reliable" intelligence that Osama bin Laden's network was involved in the car bomb attack that killed Ayatollah Mohammed Baqer al-Hakim and more than 80 others in August.
"There is intelligence information, which for us is reliable, that they had a hand in this operation,"
said Hakim, leader of the Supreme Council for the Islamic Revolution in Iraq (SCIRI).