BAGHDAD, Iraq – American officials have met figures from some Sunni Arab insurgent groups but have so far not received any commitment for them to lay down their arms, Western diplomats in Baghdad and neighboring Jordan said yesterday.

Three more American troops were killed in Iraq – two of them in roadside bombings, the American command said.

The meetings, described as being in the initial stage, have not included members of Al Qaeda in Iraq or like-minded religious extremists, the diplomats said on condition of anonymity because of the sensitivity of the subject.

Contacts have taken place in western Iraq, Lebanon,and the United Arab Emirates, according to two diplomats based in the Jordanian capital, Amman. One of them said talks might shift to Egypt “at some point.”

American officials have said establishing a dialogue with the insurgents was difficult because of the lack of a unified command structure among the various groups and the absence of a leadership capable of speaking for most of them.

An American military spokesman in Baghdad, Lieutenant Colonel Barry Johnson, said America is involved in talks on promoting Iraq’s political process with “all sorts of groups,” but declined to say if any insurgents were among them.

However, a Western diplomat in Baghdad who is familiar with the dialogue said America was reaching out to “Sunni Arab nationalists” and “some Islamists from the Shiite and Sunni sides,” many of whom have grievances about jobs and reconstruction money.

“We hear all the time that they are interested in coming in but we haven’t seen signs,” the diplomat said. “We want to see attacks stopped. The question is, can they help end the violence if they want to join.”

America is promoting efforts to form a national unity government in which Iraq’s Shiite and Kurdish leaders would offer Sunni Arab figures key positions to try to curb the insurgency.

Talks on a new government are due to begin in earnest after formal certification this week of the results of the December 15 parliament elections. Shiite religious parties won 128 of the 275 seats – but not enough to govern without partners.

Sunni Arabs have insisted that the Shiites give up control of the police in the new government because of alleged human rights abuses by the Shiite-run security services.

On Thursday, Shiite leader Abdul-Aziz al-Hakim addressed Sunni concerns when he urged security forces to obey the constitution in performing their duties.

“We call upon our faithful security forces … to continue strongly confronting terrorists but with more consideration to human rights,” Mr. al-Hakim said in a nationally televised speech at a Shiite mosque attended by 5,000 people.

A U.N. envoy, Ashraf Jehangir Qazi, met the head of a prominent Sunni group, the Association of Muslim Scholars, yesterday for talks on Sunni allegations of human rights abuses.

“We have emphasized to the Iraqi government the need to stop these nightly raids and we constantly pursue the veracity of these allegations,” a U.N. spokesman, Said Arikat, said.”We worry that if these acts continue, they can only exacerbate the same kind of violence, which will widen the gap between the two different communities.”