While Yugoslavs anxiously awaited announcements on President Tito's health, one of his oldest friends made a strong appeal tonight for national unity in a television interview that included accounts of attempts by Moscow to seize control of Yugoslavia.

Vladimir Bakaric, a top-ranking Croatian official gave his television audience a long and vivid account of how former Soviet leader Joseph Stalin failed to "liquidate" the popular Tito and install a puppet government after Yugoslavia broke from the Soviet Bloc in 1948. His account of Tito's past success coincided with a new optimistic medical bulletin that the 87-year-old president was "gradually recovering" from surgery that amputated his left leg Sunday. It was the second operation in a week for Tito. The bulletin said his general condition is "good."

Bakaric generously credited Tito and the late Edvard Kardelj, a major influence on this country's foreign policy, for having been the architects of modern Yugoslavia, but he noted that he had also taken part in shaping and implementing their policies. Political observers here said the thrust of his remarks and long historical overview was designed to create a sense of continuity in the ruling group he represents.

There was also a hint in Bakaric's remarks that he favors greater liberalization of Yugoslavia's domestic life and that the government intends to pursue with greater vigor experiments in the political "pluralism" Kardelj urged before his death.

Although billed as an interview, Bakaric's appearance was a monologue in which he frequently referred to notes on his desk. It was a low-key address apparently seeking to reassure the Yugoslavs.

But even if Tito continues to improve, it is apparent here that power is being effectively transferred to a group of Tito's associates in which Bakaric holds a pivotal position.

Bakaric, 68, has been the top communist official in Croatia, the second largest Yugoslav republic, for the past 36 years. The other two key leaders in the remarkably smooth transition are Stane Dolane, a Slovene who was former executive secretary of the Communist Party, and former foreign ministeer Milos Minic, who is a Serb. Yugoslavia has a federal government that confers substantial self-governing powers on its six ethnic groups, including the Serbs, Croats and Slovenes.

In his interview tonight, the first such appearance by a top official since Tito's health problems produced a sense of crisis here, Bakaric reaffirmed the continuity of Yugoslavia's foreign and domestic policies.

But he then struck the theme of a Soviet threat, one that has been the main unifying factor in this multinational state since it broke with Moscow in 1948.

The state of Tito's health has generated widespread concern in Europe because it raises the prospect of the first transition of power in 36 years in this independent communist country. It comes at a time when the Soviets are pursuing a more assertive course in international affairs that has prompted fears here that they may seek to reincorporate Yugoslavia into the bloc.

Bakaric recalled tonight that, before he left for Moscow to take part in the crucial negotiating session immediately before the 1948 break, Tito warned him that the Soviets "will bully you if you permit yourself to be bullied."

Bakaric said he and his two senior colleagues -- Kardelj and Milovan Djilas -- were "forced" to sign a document in Moscow pledging not to make any foreign policy decisions without Soviet approval.

The Yugoslavs were subjected to browbeating and indignities, he said. Among other things, the Soviets got the delegation out of bed after midnight to have them sign the document.

"Kardelj," he recalled, "was so furious that he inadvertently signed the pact at a wrong place and it had to be printed all over again."

The interview was ostensibly designed as a tribute to Kardelj, the main party theoretician who died in February. But Bakaric used it to deftly remind Yugoslavs of the "Eastern peril" without making direct references to the current Soviet leaders.