With relations between the military government in Thailand and the neighboring Indochinese Communist states gradually improving, authorities here are hopeful that large numbers of the 95,000 refugees here soon will return to their homelands.

Officials dealing with the refugee problem admit privately, however, that Thailand is making quiet arrangements to settle at least 20,000 Indochinese permanently in this country.

At the same time, refugees from the three Communist countries - Vietnam, Cambodia and Laos - continue to pour, 2,000 last month alone. The United States and a number of other Western countries are admitting thousands of refugees, but the numbers here are growing rather than declining.

So overwhelming has the refugee crisis become that Thai authorities are now turning back many of those crossing the border from Laos and towing Vietnamese "boat cases" back out to sea. Few Cambodians are able to escape from their tightly scaled country.

Since Nov. 15, the Thai government has been applying stringent definitions to "refugees" seeking entry.

"Until that date," said Interior Ministry official Damrong Soonthorn-saratoon, "we accepted anyone who reached this country."

Citing the U.N. definition of a refugee as a person who had well-founded fear of political persecution in his or her country, Damrong said, "We now believe the time has come to put into practice this formal definition."

A U.S. source in Bangkok said the United States did not agree with the Thai application of this definition.

"As far as we're concerned," this source said, "anyone who takes the risk to flee from the Indochinese countries has made a political commitment and should be treated as a legitimate refugee."

Privately, Thai officials complain that the United States is "dragging heels," that its screening of refugees is too slow and "takes only the cream, leaving the poorest, the uneducated, the unskilled and the potential trouble-makers for us."

One official said bitterly that the refugees were "entirely an American responsibility, because it was an American war. Yet we're the ones who must accept the brunt of the problem, just because we're in geographic proximity."

Although Thailand has established committees to study individual cases of new arrivals, several observers say border forces and naval patrols have been ordered to turn away anyone without legal documents.

"We do stop as many as we can," said Damrong, who is director general of the ministry's local administration department. "But we try to limit those we turn away to men of fighting age."

He said he did not know how many potential refugees had been turned away since Nov. 15, but that 200 Laotians, 18 Cambodians and 55 Vietnamese were being held "temporarily" for "safe repatriation" or acceptance by a third country.

A U.N. official in Bangkok said the organization had broached the subject to the governments of Vietnam and Laos, "but they weren't interested. Their attitude is they have enough internal problems without allowing these subversives back into their countries."

Damrong and other senior Thai officials said they were encouraged, though, by the announcement last week that Thailand and Vietnam will soon exchange diplomatic missions for the first time since the end of the war in Indochina more than two years ago.

Thailand and Laos have never broken relations and some observers believe that one diplomatic ties are set with Vietnam, which has a "big brother" relationship with Laos, the Laotian government will warm toward this country.

Cambodia, whose government is by far the most radical of the three, remains more distant. There have been recent reports, however, of impending negotiations between Thai and Cambodian officials to be held in the Laotian capital, Vientiane. China is known to be pressing the Cambodians to end their border hostilities with Thailand.

U.N. statistics show that 75,633 Laotians, 15,156 Cambodians and 4,105 Vietnamese are now in Thai refugee camps.

The United States has accepted 150,000 refugees since the end of the war, and a special U.S. team is currently screening another 15,000 for next summer.

Thomas J. Barnes, a State Department official in charge of the U.S. team, said 8,000 of these would come from inland camps and the other 7,000 would be Vietnamese "boat cases."

Barnes noted that the flow of Vietnamese out of the southern part of the country has increased sharply since the end of the monsoon rains two months ago. In October alone, he said, 858 Vietnamese refugees reached Thailand and another 1,254 made their way to Malaysia.

Some Western observers believe that if this level of escapes continues, the number of refugees in Thailand will reach 150,000 in another year. Thailand is hopeful that the United States, France, Australia and other countries will continue to admit substantial numbers indefinitely.

One official admitted privately that Thailand was making preliminary arrangements to integrate and settle "at least 20,000 of those already here, and possibly as many as 60,000 if we're left with no other choice."