Former Cambodian leader Prince Norodom Sihanouk met with American officials for the first time in four months yesterday to blast both sides in the ongoing Cambodian war and promote his own new, neutral national front movement, according to a participant at the meeting.

A U.S. official who accompanied American Ambassador to Peking Leonard Woodcock to the early evening meeting with Sihanouk said the former monarch described the new group formed during a recent meeting in North Korea. He said Sihanouk did not ask for U.S. aid, however, as he said he would do in a cable earlier this week to The Washington Post.

In Washington, State Department spokesman Hodding Carter said he would not rule out the possibility that the United States might support Sihanouk sometime in the future as an alternative to the "brutal Pol Pot regime or the Vietnamese puppet administration of Heng Samrin," although he said the administration has no plans to send military aid to any faction in Cambodia at this time.

"We believe Sihanouk could have a constructive role to play in finding a solution to the conflict," Carter said.

Sihanouk had said in the cable that his group, which he said controlled a Khmer Nationalist Army, already had some units operating against Vietnamese invaders inside Cambodia. Sihanouk did not repeat that claim yesterday, the American official said, but asserted that the group was ready to send troops in to repulse the Vietnamese and the government they installed in Phom Penn.

Sihanouk, who could not be reached for comment, heaped scorn on the Cambodian guerrilla force of the ousted government of Pol Pot, who kept Sihanouk a virtual prisoner in Phnom Penh for three years. He was released and came here in early January, shortly before the Pol Pot government lost the Cambodian capital to the invading Vietnamese.

Sihanouk left Peking for Pyongyang in North Korea about four months ago, apparently to allow himself a more peaceful environment for writing projects and to put some distance between himself and his Chinese hosts. Peking remains very friendly to Sihanouk and puts a hugh mansion at his disposal whenever he comes to China, but the Chinese continue to support Pol Pot's forces as the only significant armed resistance to their archrivals, the Vietnamese, inside Cambodia.

Sihanouk came here on an invitation from the Chinese to attend their 30th anniversary celebrations last weekend. Peking so far has had no public reaction to Sihanouk's plans for an armed third force in Cambodia, which he outlined this week in cables to several news organizations.

American officials said that Woodcock requested yesterday's meeting at Sihanouk's mansion here. The American ambassador had met with Sihanouk in May before his departure for North Korea and "we wanted to stay in touch," a U.S. official said. Officials indicated that the Americans wanted Sihanouk to know they were still with him in his efforts to oppose the Vietnamese invasion of his country.

In his cable to The Post, Sihanouk told of Woodcock's request for a meeting and said he would ask for technical and financial help from Washington for the new guerrilla force. But an American participant at yesterday's meeting said, "There was no request for help, not diplomatic and certainly not military."

According to the Americans, Sihanouk said he had concluded there was little hope that the Vietnamese would agree to a peaceful solution of the Cambodian issue and thus he had to commit himself to supporting an armed force. Sihanouk earlier had said the new neutral national front plan came as the result of a meeting in Pyongyang in late September of more than 30 Cambodian expatriates and representatives of various refugee groups.

Foreign analysts have speculated that the Chinese disillusioned by Pol Pot's heavy-handed methods and failure to repulse the Vietnamese, are interested in supporting a new Cambodian force against Hanoi. They are expected to do this in a very clandestine fashion, however, so as not to alienate Pol Pot. The Vietnamese, who now have an estimated 170,000 troops in Cambodia, are said to be preparing for a major offensive against Pol Pot's forces -- once the monsoon season ends in late November or early December.

There has been little independent confirmation so far of any actions by non-Pol Pot guerrillas against Vietnamese forces in Cambodia. Some sources in Thailand, however, estimate that there may be 3,000 to 10,000 anti-Vietnamese fighters in the country who have some connection to Sihanouk or other neutralist and rightist factions.