About 60,000 Cambodians, many of them diseased and starving, have massed along the border with Thailand and probably will cross over soon in search of food, a senior Thai official has announced.

His statement appeared to support earlier warnings by Indochina analysts that the growing famine in Cambodia could drive as many as a million people into Thailand.

Air Marshal Sithi Sawetawila, head of the Thai National Security Council, said in a telephone interview that the Thai army would not try to block the 60,000 from entering the country. He said, however, they would be given food and shelter only temporarily and would not be allowed into the U.N.-supported refugee camps, the usual way station to resettlement abroad.

"We'll do our best to help these people," Sithi said. His promise of only temporary haven indicated, however, that the Thais might forcibly send home the arriving Cambodians at some future date.

Vietnam's invasion of Cambodia last winter brought a new surge of refugees into Thailand. The authorities declared they would not accept refugees indefinitely and closed the U.N. camps to the newcomers. In June, about 42,000 people, most of them civilians, were pushed across the border into Cambodia's Preah Vihear Province.

Analysts said Sithi's statement might be intended to prod the United States and other countries of resettlement into taking new arrivals on an emergency basis. These people would bypass the years-long wait most refugees undergo in the U.N. camps, which now contains about 175,000 people.

Renewed fighting, prompted by unusually light monsoon rains, seems to have sped the movement of Cambodian civilians. In recent weeks troops loyal to the ousted Khmer Rouge prime minister, Pol Pot, attacked the town of Pailin, occupied by Vietnamese forces. The Khmer Rouge apparently succeeded only in capturing some territory around the town.

Western diplomats confirmed that about 60,000 Cambodians have moved westward toward the Thai border in recent weeks. The refugees are traveling on foot and foraging for food. Many are believed to have been among 42,000 forcibly repatriated in June.

News agency reports, quoting diplomatic sources, said a mass of refugees, totalling perhaps in the tens of thousands, had gathered around the town of Sisophon. Many had arrived from areas around the towns of Battambang and Siem Reap, the reports said.

Refugee workers here said another concentration of 15,000-20,000 people was located just across the border from the Thai district town of Tha Phraya. This group was first detected several weeks ago but has not tried to cross into Thai territory.

These and other people moved in hopes of finding food. The few foreigners that the Hanoi-backed Heng Samrin government has admitted to the country have reported that only a fraction of Cambodia's arable land is under cultivation and that the country's few hospitals are already full of terminal malnutrition cases.

Heng Samrin has appealed for international aid, but deliveries have been slowed by his insistence that all aid be channeled through Phnom Penh. Relief agencies fear that aid delivered to the government in this way might be diverted to support the war against the Khmer Rouge.

So far only three planeloads of emergency supplies, sent by the United Nations Children's Fund (UNICEF) and the International Red Cross, have arrived in Phnom Penh. Both agencies have succeeded in putting representatives in Cambodia to try to monitor distribution of the aid.

It appears unlikely, however, that significant volumes of aid will ever find their way from Phnom Penh to Cambodia's western provinces. Communication with the capital is poor and the strength of the Pol Pot forces is greatest there. Thus civilians there probably will continue to look to Thailand for food.

The Thai government has long believed that letting food into Cambodia would give people there less reason to try to enter Thailand. Thus the U.S.-based Catholic Relief Service quietly received clearance months ago to deliver convoys of food for distribution to malnourished Cambodians across the border. Thai merchants have been allowed to sell food and other necessities to Cambodian civilians and soldiers.

But these measures now appear insufficient to contain the problem. Sithi said the government would prepare to take in large numbers of people temporarily administering the program through a joint committee to be formed with relief agencies and foreign missions. With their help the influx would be handled without major dislocation, he said.

Indochina analysts here predicted, however, that in the months ahead food supplies in Cambodia are likely to tighten further and that the Vietnamese Army, estimated to have 170,000 troops deployed in Cambodia, will launch a dry season offensive to try to mop up the remnants of Pol Pot's army. These events, they said, could generate refugees in such numbers that 60,000 would seem like a handful.