Prince Norodom Sihanouk, the head of a coalition of Cambodian resistance groups battling the Vietnamese occupation of their country, called on China today to make good its pledge to teach Hanoi a "second lesson" following a series of major resistance defeats.

"We want China to teach Vietnam a second lesson now," Sihanouk said in an interview at this Gulf of Thailand resort, where he is staying in a well-guarded Thai government guest house.

He referred to a promise that he said was given him last October in Peking. Sihanouk said Chinese leaders Deng Xiaoping and Hu Yaobang pledged then to maintain military pressure on Vietnam's northern border and to "punish" the Vietnamese there if the Cambodian resistance suffered battlefield reverses at the hands of Hanoi's troops on the Thai-Cambodian border.

China invaded Vietnam for several weeks in early 1979 in what Peking described as a "lesson" for Hanoi after Vietnamese forces invaded Cambodia and drove out the Chinese-backed Khmer Rouge communist government under Pol Pot.

The Khmer Rouge and two noncommunist resistance groups -- one loyal to Sihanouk and the other, larger group led by former premier Son Sann -- have since been fighting the Vietnamese occupation as part of a shaky, U.N.-recognized coalition government.

Sihanouk said he was "not disappointed" at the lack of a major Chinese response so far to the recent resistance losses during Vietnam's dry season offensive in Cambodia, and he predicted that Peking would act to relieve pressure on the resistance.

The former Cambodian ruler said he had received a message from the Chinese "a few days ago" informing him that "China was determined to counterattack" the Vietnamese.

"China will continue to react very strongly against the Vietnamese in the military field in order to punish them," Sihanouk said. "But we will have to see whether the scale of the Chinese counterattack is large or medium-sized."

The prince said he and the two other resistance leaders, Son Sann of the Khmer People's National Liberation Front and Khieu Samphan of the Khmer Rouge, wanted China to move now "since now it appears that the situation of the armed resistance in Cambodia is getting bad." He added, "We are not in a desperate situation, but a bad situation."

Since the Vietnamese bagan their current dry season offensive in November, they have systematically overrun all the major bases on Cambodian soil of Son Sann's group, driving his guerrillas and civilian followers across the border into Thailand. In recent days the Vietnamese also have overrun the main Khmer Rouge stronghold of Phnom Malai in western Cambodia, capturing the group's de facto capital, Phum Thmey.

The offensive has forced almost all of the 250,000 population of the Cambodian resistance settlements to flee across the border to evacuation sites in Thailand denying the resistance groups what they called their liberated zone on Cambodian soil.

So far only Sihanouk's group, the National Sihanoukist Army, has escaped attack. But he said he feared his group and its one Cambodian base at Tatum on the northern Cambodian border, where he said about 5,000 of his fighters are based, could become "dessert" for the Vietnamese.

Despite the losses, Sihanouk said, "We are still intact as far as our manpower and weapons are concerned."

Sihanouk also expressed confidence that new tactics and supplies of weapons would help the resistance bounce back from its latest reverses. He said that in a few weeks China would deliver large supplies of weapons and ammunition to enable the resistance groups to counterattack and establish small guerrilla bases deep inside Cambodia.

The prince said he and the two other resistance leaders had agreed recently not to try to recapture their lost bases on the border but to change tactics and wage a "war of movement" in the interior.

"We have been forced by the Vietnamese to change our tactics," Sihanouk said. "We have to build up new bases, but not big strongholds and headquarters." He said these could be established in the Cambodian jungles and other areas, "because the Vietnamese cannot be everywhere."

Sihanouk said the resistance groups had already started to implement this plan, and that half of the 10,000 guerrillas in his own group have been sent "deep inside Cambodia."

He also said informants had told him that well before the Vietnamese attack on the Phnom Malai area, the Khmer Rouge had started preparing another base in the Cardamom Mountains in southwestern Cambodia.

Sihanouk said that while his own group now had a surplus of Chinese-supplied arms, he hoped the United States would provide military aid to Son Sann's group.

Sihanouk dismissed concerns that, if the resistance had its way, Pol Pot might crush his noncommunist rivals and again return to power in Phnom Penh.

Sihanouk said that if Pol Pot eliminated his rivals after an eventual negotiated solution, the Vietnamese would be well justified in invading again and would have the support of Khmer nationalists now fighting them.

Besides, he said, Pol Pot was currently "in very poor health and getting weaker and weaker physically." He said Khieu Samphan had told him last year that the former dictator, who now is the Khmer Rouge military commander, is suffering from malaria.