Cuban leader Fidel Castro urged the Soviet Union to launch a "preemptive strike" against the United States during the 1962 Cuban missile crisis, according to newly available recollections dictated by former Soviet premier Nikita Khrushchev.

"Castro suggested that to prevent our nuclear missiles from being destroyed, we should launch a preemptive strike against the United States," Khrushchev recalled. But, he added, after the Soviet Union installed 42 nuclear-armed missiles in Cuba, "My comrades in the leadership and I realized that our friend Fidel totally failed to understand our purpose," that the missiles were supposed to be a deterrent against attack, not to be used against U.S. targets.

Khrushchev died in 1971. His new recollections appear in a third volume of his memoirs that are excerpted in this week's Time magazine. He confessed that "our security organs" had told him the missiles would not be detected right away by U.S. planes. "Supposedly, the palm trees would keep our missiles from being seen from the air." But, he added, "The security people turned out to be wrong. The Americans caught us in the act. . . . "

Khrushchev, in more than 100 hours of tape recordings that fill in pieces missing from the earlier memoirs, also recalled that Julius and Ethel Rosenberg helped the Soviet Union "master the production of nuclear energy faster than we would have otherwise, and . . . helped us produce our first atom bomb."

"I was part of Stalin's circle when he mentioned the Rosenbergs with warmth," he recalled. "I cannot specifically say what kind of help they gave us, but I heard from both Stalin and {Vyacheslav} Molotov, then Minister of Foreign Affairs, that the Rosenbergs provided very significant help in accelerating the production of our atom bomb." The Rosenbergs were convicted of conspiracy to commit espionage. They went to their deaths in the electric chair in New York in 1953, proclaiming their innocence to the end.

Dictating into a tape recorder in the late 1960s, after he had been removed from office and was living under virtual house arrest in the village of Petrovo-Dalneye, Khrushchev also revealed shared attitudes with the reformer who followed him many years later, President Mikhail Gorbachev.

Sounding much like Gorbachev today, Khrushchev lamented that the Soviet Union cannot feed itself, and suggested it should "use the services of capitalism -- the system we have made it our goal to defeat. . . . "

Although repression increased in his final years in office -- he was ousted in 1964 -- on the tapes Khrushchev sharply criticizes the suppression of human rights, questioning what kind of "workers' paradise" the Soviet Union could be if "you have to keep people in chains." Denouncing what he called "the most cruel" censorship and warning that it would turn ideologues into "police bullies," Khrushchev confessed regret that he had a hand in banning Boris Pasternak's novel "Doctor Zhivago."

In this final volume of Khrushchev's memoirs to be published next month by Little, Brown, the late Soviet leader:Described Stalin as "desperate" in 1942 and said Stalin "tried to make a very secret approach to Hitler during the war." According to Khrushchev, Stalin wanted to strike a deal giving Germany territory the Nazis occupied in the Ukraine, Belorussia and even parts of the Russian Federation. But "there was never any answer from Hitler." Offered what he said is further evidence of Stalin's complicity in the shooting of Leningrad party chief Sergei Kirov, the murder that launched the purges of the 1930s. According to Khrushchev, the man who shot Kirov, a disgruntled ex-Bolshevik, Leonid Nikolayev, had come to Kirov's office earlier, been arrested and found to be carrying a gun. "Yet he was set free," Khrushchev recalled. "The only conclusion is that he was released on orders from higher-ups in the same organization who had sent him to commit a terrorist act. . . . I have no doubt that Stalin was behind the plot." Said Stalin and others in the leadership misjudged the post-World War II direction of Europe. "We had our hopes," Khrushchev said, that "after the catastrophe" of the war, and surrounded by its devastation, much of Europe -- including Germany, France and Italy -- would become communist. "Stalin wasn't the only one who incorrectly predicted this," he said. "All of us believed it." But, he added, "The powerful economy of the U.S. prevented the devastated economies of the European countries from reaching the flashpoint of revolutionary explosion. Things did not happen the way we expected in accordance with Marxist-Leninist theory. Unfortunately, all these countries stayed capitalist. . . . " Called it "a mistake to send our troops into Czechoslovakia" in 1968, the year he was dictating, because the Czech people were "our closest allies" and sending in the Soviet troops "is seen as a sign of disrespect for their government's sovereignty." Earlier, recalling debates over the 1956 invasion of Hungary, Khrushchev said one of his closest colleagues, Anastas Mikoyan, had been in Hungary trying to deal with the situation when he returned to Moscow to find the Soviet leadership had already decided to send in troops. In an emotional scene, Mikoyan protested strenuously and even threatened suicide to Khrushchev.

The new material was apparently excised from Khrushchev's earlier memoirs because of the extraordinarily blunt comments he made about Soviet leaders and important events. His son, Sergei Khrushchev, in his book, "Khrushchev on Khrushchev," published earlier this year, described how the original memoirs were written and said his father deleted "passages that might constitute military secrets and incidental references to people then in power in the U.S.S.R."

These missing tapes were obtained last year by Time. The magazine's editor-at-large, Strobe Talbott, who edited and translated the first two volumes of Khrushchev's memoirs, said "to the best of our knowledge, the Khrushchev archive is now complete" with the addition of the new material, which will be given to the W. Averell Harriman Institute for the Advanced Study of the Soviet Union at Columbia University.

Talbott said Sergei Khrushchev "has written an extraordinarily candid and useful explanation about the origins of the memoirs, and while for very understandable reasons he doesn't answer every question, he answers a great many questions" about the origins of this material. Talbott said he did not want to "go beyond what Sergei says" about the tapes.