From 1979 to 1991 Washington indirectly backed the Khmer Rouge, then a component of the guerrilla coalition fighting the Vietnamese-installed Government.

The Administration is withdrawing its recognition of the Cambodian guerrilla coalition and opening negotiations with Vietnam on settling the Cambodian conflict.

Leaders of the seven-member guerrilla coalition based in Pakistan have rejected the Government's overtures, insisting that they will have no dealings with Communists.

Peace negotiations between the Government and the three-part guerrilla coalition have been stalled by a dispute over who should govern Cambodia in the period leading up to an election.

It is now held by the guerrilla coalition nominally led by Prince Norodom Sihanouk.

Thailand, facing Vietnam's huge army on its border, has been strongly supportive of the guerrilla coalition.

In the frequent discord of the loose guerrilla coalition, Mr. Hekmatyar's wing of the split party stands out for being coherent and consistent.

"Old tactics aren't working as they used to," a senior American official said of the Farabundo Marti National Liberation Front, the guerrilla coalition.

In Jakarta, Indonesia, next week, the Vietnamese-installed Cambodian Government will meet for the first time with the three-party guerrilla coalition.

Vietnam withdrew most of its troops almost a year ago, and the guerrilla coalition has been gaining ground.