Prime Minister Nouri al-Maliki said Tuesday his government will send envoys to neighboring countries to pave the way for a regional conference on ending the rampant violence in Iraq.

The Shiite leader appeared to back down from previous opposition to handing neighboring nations a say in Iraqi affairs but stressed that the conference would be held in Iraq, and that while his government would welcome help, it would not tolerate interference.

"After the political climate is cleared, we will call for the convening of a regional conference in which these countries that are keen on the stability and security of Iraq will participate," he said.

In new bloodshed, suspected insurgents set off a car bomb to stop a minibus carrying Shiite government employees in Baghdad, then shot and killed 15 of them, the government said. In another attack in the capital on Tuesday, two car bombs exploded in a commercial district, killing 15 other Iraqis, police said.

The U.S. command said an insurgent attack on an American military patrol in Baghdad on Monday killed one soldier and wounded five. Another U.S. serviceman died in southern Iraq on Monday in an accident involving his vehicle.

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Al-Maliki's statement came a day before the Iraq Study Group, headed by former Secretary of State James A. Baker III and former Rep. Lee Hamilton, D-Ind., is to release recommendations on changing U.S. strategy in Iraq. Those are expected to include a suggestion to engage Iraq's neighboring nations, including U.S. adversaries Iran and Syria, in the search for an end to the violence in Iraq. It also is expected to recommend gradually changing the mission of U.S. troops from combat to training and supporting Iraqi units, with a goal of withdrawing the Americans by early 2008.

Other Shiite politicians, including Abdul-Aziz al-Hakim, who leads the largest Shiite bloc in Iraq's parliament, have in recent days rejected a suggestion for an international conference by U.N. Secretary-General Kofi Annan. The outgoing U.N. chief said such a gathering could be useful if the political parties involved met outside Iraq.

Al-Maliki said the proposed regional conference would be held in Iraq at the invitation of his government and would offer help, rather than solutions, to his government's ongoing efforts to curb spiraling sectarian violence.

Al-Maliki also said a frequently delayed national reconciliation conference designed to rally the country's various ethnic, religious and political groups around a common strategy for handling Iraq's problems would be held later this month.

He added that he planned to shortly announce a reshuffle of his six-month-old government "to boost the effectiveness and strength of the national unity government," but he gave no details.

The latest American deaths came after a weekend in which 13 American service members died in Iraq, including four whose Sea Knight helicopter plunged into a lake in volatile Anbar province, the military said.

The Defense Department identified one of the four dead as Army Spc. Dustin M. Adkins, 22, of Finger, Tenn., who was assigned to the Group Support Battalion, 5th Special Forces Group, Fort Campbell, Ky.

In northern Baghdad, gunmen set off a car bomb to intercept a minibus carrying employees of the Shiite Endowment, a government agency that cares for Shiite mosques in Iraq, to work, the organization said. The gunmen then opened fire on the workers, killing 15 of them and wounding seven, said Salah Abdul-Razzaq, an Endowment spokesman.

AP Television News video showed shattered glass and shoes in the middle of the highway, with the burned-out hulk of the car that exploded on the side of the road.

A similar attack occurred late last month in southern Iraq against the Sunni Endowment, the government agency that cares for Sunni Arab mosques in Iraq.

On Nov. 30, gunmen fired at a convoy carrying an official from that agency, killing him and three of his bodyguards, police said. The attack, which also wounded two bodyguards, occurred in Basra, the largest city in mostly Shiite southern Iraq, a police spokesman said. Nasir Gatami, the official who died, was the deputy of the Sunni Endowment chapter in Basra. All the victims were Sunnis.

On Nov. 15, suspected Shiite militiamen kidnapped three employees of the Sunni Endowment in Baghdad, the agency said. At the time, Ahmed Abdul Ghafour al-Samaraie, the head of the Sunni Endowment, was quoted by Sunni-operated Baghdad Television as urging al-Maliki to work for the men's release.

In another attack in the capital on Tuesday, two car bombs exploded near one another in western Baghdad, killing at least 15 people and wounding 25, police said.

The explosions occurred at about 9:45 a.m. near a gas station in Baiyaa, a commercial area of the capital with a mixed Sunni Arab and Shiite population, a policeman said on condition of anonymity because he is not authorized to speak to the media.

On Monday, insurgents attacked a U.S. Army patrol in Baghdad as it was trying to control the movement of insurgents and enforce curfew restrictions in a northeastern neighborhood of the capital, the military said.

In southern Iraq, a 13th Sustainment Command (Expeditionary) soldier died Monday when his M-1117 Armored Security Vehicle rolled over north of Camp Adder, which is 200 miles southwest of Baghdad, the military said.

The deaths raised to at least 2,904 the number of members of the U.S. military who have died since the beginning of the war in 2003, according to an AP count.

President Bush told one of Iraq's leading Shiite politicians, Abdul-Aziz al-Hakim, in a White House meeting Monday that the United States was not satisfied with progress in Iraq.

"I assured him that the U.S. supports his work and the work of the prime minister to unify the country," Bush said, referring to Iraqi Prime Minister Nouri al-Maliki. "Part of unifying Iraq is for the elected leaders and society leaders to reject the extremists that are trying to stop the advance of this young democracy."

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