UNITED NATIONS, AUG. 6 -- The United States and Vietnam held their first formal talks on Cambodia today, seeking a peace settlement to end the 20-year-old civil war that has led to the deaths of millions of Cambodians.

"The American and Vietnamese sides have presented their views . . . especially on the issues of self-determination of the Cambodian people through general elections, restoration of peace and prevention of the Khmer Rouge's return to power," Vietnam's U.N. ambassador, Trinh Xuan Lang, told reporters after the 3 1/2 hours of discussions at Vietnam's U.N. Mission.

The Communist Khmer Rouge has drawn world condemnation because of the deaths of more than 1 million Cambodians through executions, starvation and forced relocation when it ruled the nation from 1975-78.

Lang led Vietnam's team of representatives at the U.N. meeting and the U.S. delegation was led by Kenneth M. Quinn, deputy assistant secretary of State for East Asian-Pacific Affairs.

Lang said the talks also dealt with the "the role of the United Nations and international guarantees on the neutrality of Cambodia."

Most nations favor a cease-fire in Cambodia, followed by general elections to establish a new government.

Differences exist over the role the Khmer Rouge or the Hanoi-backed Phnom Penh government would have in any transitional administration, which would be supervised by the United Nations.

Quinn said they also dicussed the "POW-MIA" issue, referring to American personnel still listed as missing in Indochina. U.S. officials say 2,300 Americans remain missing in the region, including 1,678 in Vietnam.

On July 18, Secretary of State James A. Baker III announced that the United States was withdrawing its recognition of the Khmer Rouge-dominated resistance coalition fighting the Cambodian government and would begin talks with Hanoi.

Lang described the talks as "businesslike," and said, "We think that there is a better understanding." More U.S.-Vietnam talks will be held soon, at a time and place to be agreed upon, both sides said.

Lang said, "Of course, it is better if the United States could have direct talks" with the Hanoi-backed government in Phnom Penh, and said his delegation was conveying the views of Cambodian Premier Hun Sen.

After Vietnam invaded Cambodia in 1978 to oust the Khmer Rouge, the United Nations and most nations recognized the Cambodian resistance coalition and refused to recognize the government installed by Vietnam.

Since Vietnam said last year that it withdrew all its troops from Cambodia, the Khmer Rouge has scored impressive military gains in the field, prompting many policy makers in Washington to argue that keeping them from seizing power again should be the prime goal of U.S. policy in Cambodia.