The story was, in journalistic terms, an earthquake. it confirmed that Khrushchev had indeed made his rumoured speech denouncing Stalin

Special report - A pawn in a dangerous game that went right to the heart of Soviet power politics or

Into the early hours of 26 February 1956, the windows of the Communist Party's Central Committee building in the heart of Moscow were alight. Black limousines of the party elite were parked all around. This, it seemed to western observers, was odd. The 20th Congress of the Soviet Communist Party (CPSU) had formally ended that afternoon. So why was party headquarters still humming with activity?

Over the next few days the rumours spread, fuelled by western diplomats with good connections to central European communist colleagues and by western correspondents of communist newspapers. It was whispered that Nikita Ser-geyevich Khrushchev, the First Secretary of the CPSU, had made a sensational speech denouncing Stalin for crimes such as murder and torture. Coming only three years after Stalin's death, this seemed barely credible. True, for months the rigidly controlled press had been attacking the "cult of personality", a veiled reference to Stalin. This criticism had reached a cres-cendo during the 20th Congress, though only Anastas Mikoyan, Khrushchev's right-hand man, had been authorised to criticise Stalin by name in a published speech. Even then he was cautious. But torture and murder?

The rumours in "diplomatic circles" suggested, however, that something unprecedented had happened: a furious personal denunciation of the man who, until then, had been looked upon as God by the overwhelming majority of the population. Now, it seemed, God had been cast down.

Yet nothing appeared in the official media. The rumours could not be substantiated. But they were so insistent that Sidney Weiland, my bureau chief at Reuters, decided to file a brief news report about them. In those days, however, western correspondents were required to send their stories from a special office in the Central Telegraph building. Weiland handed in his story for cabling fully expecting it to be censored. He was right; it vanished into the censor's maw and was not heard of again.

Khrushchev's speech was an unspeech. He himself never publicly admitted making it. In fact, on the morning of 25 February, delegates to the 20th Party Congress had entered the Grand Kremlin Palace, without their foreign comrades, to be stunned by his tirade against their revered leader. A few days later, at the beginning of March, I received a phone call from Kostya Orlov, a Soviet citizen I had met several times. "You're going on holiday to Stockholm tomorrow," he said. "I must see you before you go."

It was my last evening, so I invited him round at once. He had often been to my flat in a block reserved for foreigners, and had experienced no difficulty getting past the militiamen who guarded the entrance from intrusion by Soviet citizens. Orlov was an intelligent young man with a tinge of sleaziness about him, and not infrequently drunk. He lived on the ground floor of a squalid communal dwelling, in one of many small rooms off a long corridor, at the end of which was a kitchen, a toilet and a shower room for all on that floor to share. His was a common experience.

I first met Orlov the previous year when I went to cover the arrival of French tourists - the first independent westerners to visit since the Second World War. He was trying to befriend them outside their hotel, though without the advantage of any language but Russian. We fell into conversation. Over the next few months I saw quite a lot of him, visiting him occasionally in his solitary room, but more often when he came to my flat.

This was so unusual that I had little doubt he was controlled by the KGB, though he always denied it, claiming to hate Soviet life; he even asked me if I could spirit him out across the Finnish frontier or smuggle him out on a plane. He knew that I was then married to a Finn, had lived in Finland and was close to the Finnish embassy and Aero (as Finnair was then called) - the only western airline flying into Moscow. What made me even more suspicious was that he offered to smuggle me into a Moscow factory if I would put on local clothes, poorly made and horribly unfashionable, and masquerade as a Soviet citizen. "Your Russian's good enough for you to pass as a Latvian," he explained. He told me a lot about Soviet life and passed me snippets of minor information that all proved correct. The best was a brief Central Committee resolution on pig production, which sent the US agricultural attache, to whom I showed it, into paroxysms of delight. "This is just what we've been looking for," he chortled with glee.

The two stories Orlov brought me that evening, a week or more after the 20th Party Congress, were no snippets. The first was an earthquake. He confirmed that Khrush-chev had indeed made the speech denouncing Stalin, and without any notes gave me a full account of it. His memory was prodi- gious, almost photographic, though I was not to know that at the time. His version included two items that were not in the edited version leaked from the Polish Communist Party, which fell into the hands of the CIA and was published by the New York Times early in June. One was Khrushchev's description of how Stalin often humiliated those around him, using the familiar "thou" instead of the more formal "you", as one would to servants or children. "Once he turned to me," Khrushchev declared, "and said: 'Oi, you [thou], khokhol, dance the gopak.' So I danced." The gopak is a fast and intricate Ukrainian dance in the execution of which Khrushchev, a portly man, would have looked ridiculous. Khokhol is a derogatory term for a Ukrainian, Stalin knowing full well that Khrushchev had worked for many years in Kiev, most recently as party leader.

The second story concerned a delegate who, incensed by Khrushchev's description of Stalin, shouted: "Why didn't you get rid of him?" Khrushchev stopped and looked round the hall. "Who said that?" he barked. No one spoke. So he repeated: "Who said that?" Still no response. "Now you understand why we didn't try anything against him," he said drily.

Orlov told me that when the speech was read out to party organisations in Georgia, Stalin's homeland, crowds rioted in protest against the "insult" to their national hero, and a number of civilians and Soviet soldiers were killed. In addition, Orlov said, trains from the Georgian capital, Tbilisi, had been arriving in Moscow with smashed windows. This was a sensational story in its own right, though it paled into insignificance beside the speech itself.

My problem was: could I believe him? It is easy now, with hindsight, to realise that of course what he told me must have been true. But it was a colossal risk to believe such a tale from a single and somewhat dubious source, with little corroborating evidence, and to stake the authority of Reuters on it. I had only a few hours to make up my mind before flying to Stockholm. That raised another problem. In the 1930s many foreign correspondents had found censorship so restrictive that they often flew to the capital of then independent Latvia, Riga, to file their stories before returning to Moscow. Surprisingly, the Soviet government did not object. But after two decades of Stalinism no western correspondent dared to do the same in the 1950s. At the very least, expulsion would have resulted, if not worse.

I didn't know what to do, so I called Weiland, my boss. It was nearly midnight, but we agreed to meet on the street outside the Central Telegraph office, where no hidden microphones could overhear us. It was a very cold winter, and we tramped through the snow as I recounted the tale, pausing from time to time under street lamps to consult my voluminous notes. In the end we decided we had to believe Orlov. His tale fitted with what little the foreign community knew, and he had been reliable in the past. Besides that, a New York Times correspondent was also flying out the next day and we suspected he would immediately report on the rumours. We would be beaten on a story of which we had an incomparably better - and exclusive - account. Unthinkable!

Orlov had to be genuine. "If you don't get it out, you're govno [shit]," he had told me. Ironically, this now sounds suspiciously like a strong hint from the Soviet authorities to break the rules. So the next day, feeling tense, I flew with my wife to Stockholm, the fat notebook burning a hole in my pocket. We were to stay a fortnight with Finnish diplomats who had been transferred from Moscow, but I could not let them know that I was to be the author of the report that would be published all over the world the next day. We stayed in a hotel for the first night, much of which I spent typing out the two stories and dictating them by telephone to London. I had spoken earlier to the news editor and explained that under no circumstances should either story bear my name or even a Moscow dateline, and that the speech had to be based on "communist sources" - no others were possible.

When I was ready, Reuters called me back and put me through to "copy" - the copytakers. I was extremely nervous and assumed a false American accent to disguise my identity. In vain. "Thank you, John," said the familiar voice when I finished my long dic-tation. When the Swedish papers appeared with Khrushchev's "Stalin Sensation" splashed across the front pages, it was datelined Bonn, with the riots in Georgia sourced from Vienna.

My return to Moscow passed off without incident, but when I next saw Kostya I still thought it advisable to tell him that the story had already been published by the time I reached Sweden. I doubt if he believed me, but the political thaw that had started 18 months earlier continued into the summer of 1956. It was not until October that the turmoil fomented by Khrushchev's speech burst upon central Europe, notably in Poland and, above all, Hungary.

In Moscow the thaw switched instantly into deep-freeze. During October, around the time of the Soviet military intervention in Hungary, not one top Soviet official appeared at diplomatic receptions to drink and chat with the bonhomie of the past two years. When they reappeared, they looked haggard and drawn; Anastas Mikoyan, in particular, seemed to have put on years. On the streets, Muscovites turned hastily away from any friendly approach by foreigners. There had been other incidents of un- rest when the secret speech was read out to Communist Party and Komsomol (Communist Youth) meetings. Georgia was the most violent (Orlov had told me only part of the story), but some meetings elsewhere, notably Siberia, were more than unruly, particularly where students were involved. The threat to stability at home and abroad forced Khrushchev to tone down his programme of de-Stalinisation.

I saw little of Orlov over the next few months, not least because one evening, while my wife was in Helsinki, he brought a "friend" round to see me, a large Georgian. Both got very drunk, but the Georgian made repulsive homosexual advances and broke several bottles of wine. When I finally got rid of them it took until 4am to clean up the mess.

Soon after, I gave a party for friends, mostly western journalists, including a close Yugoslav friend who warned me that Orlov was a provocateur. At that point Orlov himself arrived, unannounced, in the company of two more "friends". Both were Russians, one of whom I had met briefly at an official function. Orlov became drunk and aggressive again, leaving in high dudgeon when I told him to go. One of his "friends" apologised for him, but stayed on at the party and said we must keep in touch. It was not this man but a contact of his who phoned shortly after, inviting me to lunch. There he announced himself to be a captain of the KGB.

After four weekly lunches, with lavish amounts of vodka, caviar and smoked salmon and no shortage of menace, I finally cracked. Instead of attending the next week's lunch invitation, I asked the British ambassador to send a message to Reuters seeking my recall. Over the next few weeks I was followed ostentatiously about the streets by KGB agents. In the tension of the time, I assumed that this mounting pressure was in some way connected with Khrushchev's speech, and might be building up to some kind of retaliation. But on reflection I concluded that it was merely the kind of pressure the KGB often exerted on many foreigners, in the hope of persuading or blackmailing them into becoming a KGB agent, or to denounce the west and remain in Moscow.

More significant is the question of who told Orlov to leak the speech, and why to me. That he was operating independently is inconceivable. When I returned to Moscow 32 years later for the Guardian, I made inquiries. This was before the collapse of the Soviet Union and KGB files were not yet available to westerners for selective inspection. But a veteran journalist on Moscow News, who interviewed me about the speech, told me I would never find out. "Even if it was Khrushchev," he said, "you would find nothing in any file. Remember it was a party decision that the speech should not be published - and in any case he said himself: 'Comrades, we must not wash our dirty linen in public.' Even he could not have risked putting any instruction on paper, and perhaps not even on the phone. If he did issue an instruction, it would only have been by a quiet word to someone he trusted implicitly."

I had a very similar response from Sergo Mikoyan, the son of Anastas. "It was quite likely to have been Khrushchev," he told me, "possibly with my father's support. My father was the only colleague of Khrushchev to urge the exposure of Stalin from the first, and his strongest supporter in this throughout. But any decision to use you to tell the world about the speech would have left no trace." There is, however, strong evidence that Khrushchev wanted his speech to be widely known. In his biography of Khrushchev, William Taubman quotes his son Sergei as saying: "I very much doubt that Father wanted to keep it secret. On the contrary! His own words provide confirmation of the opposite - that he wanted to bring his report to the people. Otherwise all his efforts would have been meaningless. The secrecy of the sessions was only a formal concession on his part."

If this was indeed true, the selection of me as the conduit was logical. In those days foreigners in Moscow had to get exit visas to leave the country, so the authorities were aware of my imminent departure to Stockholm. Like other western journalists, I was also quite well known to Khrushchev and other members of the party's presidium, as they were all talking eagerly to us (some, such as Molotov, less eagerly than others) at diplomatic and Kremlin receptions - often as much as once a week. I had even, on one occasion, drunk Khrushchev's glass of aquavit when he thrust it at me in the Norwegian embassy, saying: "This is a lot better than that whisky we had in your embassy last week - here, try it!"

From the summer of 1954, when they started coming to receptions, Khrushchev and his colleagues used us journalists as the quickest means of showing the world that they were people you could do business with, not ogres like Stalin, immured behind the Kremlin's walls. To use one of us to publish the speech abroad, by bending the rules we worked under, needed only discretion and a buffer such as Orlov, who could dissociate any Soviet authority from responsibility.

In fact, in 1956 Orlov had told me that a friend of his, who was the party secretary of an institute, had been given the speech to read to the institute's party members; this had to be done only once so that they could not study it in detail. He said his friend had to hand the speech back to headquarters within 36 hours, but had allowed him to read it during this time. This he presented as something he had done on his own initiative just to help me. Thirty-four years later he still hotly denied that he had any connection with the KGB. After publication of an interview I gave Moscow News in 1990 on how I obtained the speech, Orlov, with whom I had had no contact since the 1950s, rang me in a fury to complain that I had described him as a stu-kach (an informer).

So I went to see him, but during a long discussion I could not shake his insistence that he had been acting on his own. Repeatedly walking unhindered past the militiamen guarding the foreigners' block I lived in, offering to take me to see a factory if I wore Soviet clothes, and giving me details of the speech itself were all done just to help me "because you were so green", he said. "But what about asking me to get you out to Finland on a Finnish plane?" I objected. "Or helping you to get across the Soviet-Finnish border? After all, you told me you hated living in the Soviet Union."

"Oh, you just made all that up," he said. Perhaps the only response possible, when he could hardly claim he had suggested that just to help me. So I told him there was no point in us talk- ing any more, and left.

At the time I felt that Mikhail Gorbachev's perestroika and glasnost had gone far enough for him to have admitted the truth to me in private and told me just how the leak had been arranged. But perhaps I was unfair. If indeed the order had been given by Khrushchev, then the ultimate agent, Orlov, must surely have been told that he was on his own, and that on pain of something like death, he must never reveal anything. Even in 1990, the KGB could frighten some people, and who knows what hold they had over him?

A longer version will be published in History Workshop Journal 62 in the autumn, as part of a symposium of eyewitness accounts of the events of 1956. John Rettie features in a Radio 4 documentary on the secret speech on 24 February at 11am