Soviet policy before, during and after the Six Day War has been studied extensively. Its most visible aspect – breaking off diplomatic relations with Israel – cast a deep shadow for decades over Israel's relations with the Soviet bloc, to be overcome only during Gorbachev's perestroika.

Now a surprising source has become available from the archives of the Hungarian Communist Party, recently discovered by Prof. Andras Kovacs, director of the Jewish Studies Program at the Central European University in Budapest and published by him in Vol. III of the program's Yearbook.

The source is a verbatim account of a report made on June 13, 1967, by Janos Kadar, secretary-general of the Hungarian Communist Party, to his party's Politburo. In informal language, aimed only at the top echelons of the party, Kadar reports about a hastily arranged secret summit meeting of the leaders of all communist parties held in Moscow on June 9 in response to the war.

What transpires from Kadar's report is the utter disarray Israel's victory created in the Soviet bloc. Again and again Kadar refers to the enormity of the Arab defeat and the humiliation it caused the Soviet bloc. He tells his colleagues that "many things may not be said outwardly: for instance, we cannot say that 90 percent of the Arab army is illiterate," hence could not use adequately sophisticated Soviet armaments. He contrasts this with Israel, which has "more highly qualified and skilled human resources," then adds – obviously echoing typical stereotypical thinking about intellectual Jews, that "people which primary education were set against university graduates."

Yet the most interesting part of the speech, however, concerns Yugoslavia. The emergency meeting in Moscow was the first communist summit attended by Tito since he broke with Stalin's Soviet Union in 1949, and Kadar mentions the significance of his attendance.

THE DOCUMENT shows two aspects connected with Tito which are novel. Tito – having close ties with Nasser through their joint leadership, together with India's Nehru and Indonesia's Sukarno in the Nonaligned Bloc – turns out to have been much more supportive of Nasser than the Soviets.

First of all, Kadar recounts several times that Nasser did not consult with the Soviets about his moves of closing the Gulf of Aqaba and the withdrawal of UN troops from Sinai: this is important – though not totally conclusive – evidence about the lack of Soviet involvement in Egypt's decisions. On the other hand, Kadar reports that "Comrade Tito said that they had consulted with them and that they had supported these measures."

Kadar adds that this is understandable, since the Yugoslavs "have an old and close relationship with Egypt, that is older and more permanent than the Soviet relationship."

He further says that Tito had also agreed immediately to the establishment of an emergency arms airlift to Egypt.

This put Tito's attitude to the Middle East – and his responsibility for the outbreak of the Six Day War – in a completely new light. For all of his traditional support for Nasser, Tito has been considered in the West as a responsible, independent leader: it now transpires that he was much more pro-Arab than the Soviets, and bears responsibility for Nasser's disastrous slide into the war. One can imagine what would have happened if Tito had tried to dissuade Nasser from closing the Straits of Tiran.

Tito's radical attitude re-appears several times in Kadar's report (and it should be viewed as credible, given Kadar's general praise for Tito). Again, it was Tito who introduced the draft communiqu which branded Israel as an aggressor. Many other delegates very unhappy with some aspects of the language proposed, and Kadar reports how there was some discussion about what should go into the communiqu , some suggesting "US and British imperialism" should also be condemned. It was the Romanians who opposed branding Israel as an aggressor, and it was Tito who said that unless this was included "he will not be able to go home, for we have told the whole of Yugoslavia who is the aggressor."

Kadar, for his part, adds that "although we will not probably write it in the newspapers, it must be stated clearly in party debates that the socialist countries have never supported the Arab propaganda formulations that Israel must be destroyed."

The text of Kadar's speech is unique in its frankness as it provides a glimpse into the internal working of the Soviet Bloc system under crisis: far from showing a uniform approach, one sees disagreements and nuances. Also, the Romanian position – Kadar reports in detail how the Romanian delegation openly disagreed with Brezhnev – already foreshadows the independent Romanian line towards Israel: when all communist countries – again following the lead of Yugoslavia – broke diplomatic relations with Israel, Ceausescu's Romania maintained its independent position and refused to follow the Soviet line.

But what is most revealing in this document is the radical anti-Israeli line of Tito, which must come as a surprise to many Israelis who always had a deep admiration for the hero of the anti-Nazi Yugoslav partisans: because of his World War II record, many Israelis were ready to take in their stride Tito's neutralist alliance with Nasser. But that it was Tito – rather than the Soviets – who was consulted by Nasser about the steps that led to the 1967 war, and that he supported Nasser's aggression (which also delegitimized the role of the UN) – is an unwelcome and sobering revelation.

The writer is a former director-general of the Foreign Ministry.