Romania's highest policy-making body gave its full support to President Nicolae Ceausescu tonight in his latest confrontation with the Soviet Union over defense policy.

In what seems to be part of an orchestrated campaign to demonstrate public support for the 60-year-old Romanian leader, the Communist Party Central Committee was called into special session to hear a report by Ceausescu on his stand at last week's summit meeting of the Soviet-led Warsaw Pact.

The session unanimously endorsed his opposition to proposals to increase the pact's defense budget and tighten integration among armies of member countries.

Ceausescu's stand was dramatically pointed up Tuesday by erroneous reports from Yugoslavia that all six Warsaw Pact ambassadors, including that of the Soviet Union, had been called home from Bucharest for consultations. The "crisis" waned quickly when three of those ambassadors turned up that same evening at a reception in Burcharest.

There was no way of telling whether the Yugoslav officials who started the reports were doing public relations for Ceausescu - as they have in the past - but in any case the outcome was to draw attention to Ceausecu's assertion of Romanian independence in a way that cannot be attributed to him directly.

Foreign diplomats in Buhcarest believe that, after several years of uneasiness, relations between Romania and in Warsaw Pact allied have reached their lowest point in a decade. The Central Committee session is intepreted as a sign that Ceausescu is unlikely to make any move to heal the rift in the near future and is preparing to face the inevitably angry Soviet reaction to his unprecedented public disclosures.

In Moscow, President Leonid Brezhnev indirectly confirmed Ceausecu's disclosures by calling for the "preservation and strenghtening of the joint armed forces of the Warsaw Treaty" in a report to the parliament on last week's summit. He said this was necessary in view of the continuing arms race conducted by NATO states.

A nearly identical statement was issued in Warsaw after a meeting of the ruling Polish Politburo that formally endorsed all the decisions taken at the summit. Other Warsaw Pact countries are expected to fall into line shortly, if they have not already done so.

According to the official Romanian news agency Agerpres, the Central Committee session heard over 100 statements supporting Ceausescu's stand, which the committee said "reflected the vital interests of the whole nation" and were "in line with Romania's continued progress and welfare."

In a resolution, the Central Committee reaffirmed its support for a statement by Ceausescu on Monday that "Romania's armed forces will never be committed to combat except by decision of the supreme leading bodies of our party and state." This apparently referred to his refusal to accept a more unified military command of Warsaw Pact troops as proposed by Moscow.

Interest now centers on a major foreign policy speech Ceausescu will deliver Friday at celebrations marking the 60th anniversary of the incorporation into Romania. Western diplomats believe he likely to forcefully defend his actions but unlikely to provoke a total breach with the Warsaw Pact at this time.

The 17-year-history of Romania's transformation from one of the most docile of Soviet allies into the most nationalistic has been a series of carefully calculated gestures.

At each step, from the original quarrel with Moscow in 1961, over economic integration, to last week's refusal to agree to an increase in military spending, the Romanian leaders have succeeded in pushing out the limits of Soviet tolerance and increasing their own freedom of action.

Important elements in this strategy have been mobilization of domestic support for the Romanian leadership and an eagerness to develop good relations with foreign powers, including the United States and China, as a counterbalance to ties with the Soviet Union. Romanian leaders also have been quick to appreciate the value of Western publicity for each increment in national independence as the placing on the record of what they have been allowed to get away with.

Given this background, the interesting point is not why Ceausescu should have again defied the Soviet Union, but why he has chosen to do so now and in such a dramatic manner.

The most obvious answer is that he thinks his gamble will succeed. With his political skills and long experience of dealing with Soviet leaders, he evidently has calculated that Brezhnev has enough problems of his own already and is unwilling to be drawn into another crisis in Eastern Europe.

At the same time, the opening of a more active era in Chinese foreign policy has provided Romania with the opportunity to increase room for maneuver as well as giving it a new cause of friction in its relations with the Soviet Union.

By playing host to the Chinese leader, Hua Kuo-feng, in Bucharest in August, Ceausescu was demonstrating the limits of Soviet power in Eastern Europe.

But another factor affecting the timing of ZCeausesu's latest gesture is domestic Romanian politics. If one of his primary aims since succeeding Gheorghe Gheorgiu-Dej as Romanian leader in 1965 has been to steadily strengthen Romania's independence, another has been to remain in power himself. This he has done by a combination of removing political opponents and exploiting his people's dislike of the Russians.

Ceausescu probably reached the peak of his personal popularity in 1968 when he, alone of all Warsaw Pact leaders, refused to support the Soviet invasion of Czechoslovakia. Thousands of Romanians, including the now exiled dissident Paul Goma, applied to join the Communist Part, which they identified with national aspirations.

Since 1968, however, growing public disillusion has set in against Ceausescus leadership. Unlike the Yugoslavs, who have access to Western goods and are allowed to travel abroad, ordinary Romanians have so far experienced few tangible benefits as a result of their country's independent foreign policy.

National independence and the need to turn Romania into a strong industrialized state has been used as an excuse by Ceausescu for demanding greater scarifices from the population.

Over the last couple of years, there has been evidence of mounting public discontent over what are probably the lowest living standards in Eastern Europe. The most dramatic outburst was a three-day strike by about 35,000 miners in the country's western Jiu Valley region last year, which ended only when Ceausescu himself made on-the spot concessions.