Yugoslav President Tito today called on nations of the nonaligned movement he helped found to "strive against everything that divides us and resist all attempts to insinuate alien interests into our ranks."

In what was widely billed as a reply to Cuban President Fidel Castro's bombastic speech opening the sixth nonaligned summit here yesterday, Tito recalled the "authentic" principles of the organization and warned that divisions would lead to world instability.

A number of representatives seemed disappointed in what they described as Tito's "gloves on" appeals to unity following expectations that the 87-year-old president would match Astro blow for blow.

While internal movement divisions are publicly disclaimed, many members of the 94-member organization see the current summit as a contest in both substance and style for movement leadership between Castro and Tito.

Tito is viewed as the spokesman for the moderate and neutral nations in a perceived Cuban attempt to concentrate the movement's criticism of bloc politics on the United States and pull the organization closer to the Soviet orbit and into a more militantly activist role.

On specific issues facing the summit, the Cuban effort includes harsh censure or even expulsion of Egypt for its peace treaty with Israel and recognition of the Vietnamese invasion of Cambodia as a legitimate means of replacing a repressive government here.

Tito reportedly revised a planned speech yesterday after Castro's remarks. But rather than adopting Castro's impassioned style, the Yugoslav leader opted for low-key statesmanship.

Although he appeared spry for his years, climbing the stairs to the dias unassisted, Tito did not talk from the lectern used by other speakers but from a chair at a small desk placed on the dias. The trip to Cubas, he said was "long and, for me, strenuous."

He came to Havana, Tito said, because of "the responsibility resiting upon me as one of the founders of the movement and by the firm conviction that there is no sacrifice one should not be prepared to make when such lofty objectives and noble ideas are in question."

Tito made repeated references to the beginnings of the nonaligned movement. Clearly referring to what some see as pressure for a different movement direction, he expressed his belief that its early foundations are still firm.

"Recalling the days of nonalignment," he said, "I can say that we were then and are today fully aware that the struggle for national, political and economic emancipation is an imperative."

In implied references to both the United States and the Soviet Union, Tito said, "we have from the very outset been consistently opposed to bloc politics and foreign domination, to all forms of political and economic hegemony," In nonaligned language imperialism is seen as a euphemism for the United States, while hegemony refers to the Soviet Union.

"we have never been anyone's rubber stamp," Tito said.

He added his support to the nonaligned concesus demanding economic equality, condemning South African racism and its economic support by the West, support for other southern African liberation movements and objection to Egypt's attempt to find "a separate solution" to the Middle East problem.

Although he made no direct refernce to Cambodia, Tito condemned "the imposition of foreign will on peoples by military interventions" as "totally incompatible" with nonaligned principles.

Reactions to Tito's speech were varied. Cuba and its nonaligned backers, including much of the Arab bloc, found it "weak." Others praised its appeal to unity rather than to more parochial bilaterial issues.

For some, however, it marked an admission that movement leadership is about to be turned over to more youthful, or at least more militant, members.

"Castro confidently flung down his glove," said Singapore Foreign Minister and nonaligned moderate Sinnathamby Rajaratnam, "and said, 'You pick it up.' The old man said, 'I'm too tired. You pick it up."