Asia's noncommunist nations today endorsed proposals for an anti-Vietnamese coalition government of three Cambodian resistance groups, but appeared to back away from suggestions that they would then give the groups military aid together.

Concluding a one-day meeting at this resort, the foreign ministers of the Associaton of Southeast Asian Nations (ASEAN) issued a statement backing proposals Singapore put forward last month to break a deadlock in the Cambodian groups' efforts to form a coalition government.

The proposals provide for a "loose coalition government" in which the ideologically divided groups would retain their separate identities.

The ASEAN statement noted that two of the Cambodian groups -- the anticommunist Khmer People's National Liberation Front, led by former prime minister Son Sann, and the Moulinaka faction of former Cambodian head of state Prince Norodom Sihanouk -- had expressed "their full support for these proposals."

The third and most powerful resistance group, the communist guerrillas of Cambodia's ousted Khmer Rouge government, has said it will reply in two months.

Unlike Singapore's statement, issued Nov. 24 in Bangkok after talks with the three factions, the statement today made no mention of pressing Hanoi militarily to end its occupation of Cambodia. The Vietnamese invaded their neighbor in December 1978 and installed a protege government the following month.

The ASEAN foreign ministers made clear, however, that their acceptance of Singapore's plan for a Cambodian coalition meant that the five member countries could give military aid individually to groups in the coalition.

Conference participants said clarification of this point became necessary when Indonesia expressed strong oposition last week to the idea of ASEAN's providing arms aid to Cambodian resistance groups.

On his arrival in Thailand, Indonesian Foreign Minister Mochtar Kusumaatmadja insisted that ASEAN should stick to its original purpose of economic and political cooperation rather than take on a military character. ASEAN includes Thailand, Malaysia, Indonesia, Singapore and the Philippines.

At a joint news conference concluding the meeting today, Mochtar said he was "satisfied that the coalition proposal was just that" and not something that would entail an ASEAN military commitment.

The foreign minister of the Philippines, Carlos Romulo, seconded this view, saying that "we didn't want to follow in the footsteps of the late lamented and defunct SEATO." He was referring to the Southeast Asian Treaty Organization.

Singapore's foreign minister, Suppiah Dhanabalan, said that ASEAN as a group was "committed to a political solution" in Cambodia and that it was up to the Cambodian resistance groups to provide the military pressure on the Vietnamese.

However, last month, Singaporean Deputy Prime Minister Sinnathamby Rajaratnam said in Bangkok that his tiny city-state was willing to give military aid to the noncommunist groups in an eventual Cambodian coalition. He urged other countries -- especially Western democracies such as the United States -- to contribute arms aid also.

His remarks coincided with the start of a fund-raising tour of North America and Europe by Son Sann in an effort to build up his noncommunist "third force" along the Thai-Cambodian border.

Malaysian Foreign Minister Tan Sri Ghazali Shafie told reporters that the group essentially had agreed that arms aid to the third force "cannot be an ASEAN project" and should be played down. But he stressed that, even without a coalition, a way had to be found to give "beef and teeth" to the third force.

"Otherwise, it would become a 'third farce,' " he said.