A leading Russian business daily says its top military correspondent, who died last week after falling from a fifth-floor window, had evidence at the time of his death that Russia planned to provide sophisticated weaponry to Syria and Iran.

Ivan Safronov (file photo)

Russia's Kommersant newspaper said Tuesday, that reporter Ivan Safronov was warned he would be charged with revealing state secrets, if he reported that Moscow had signed a deal with Syria for the sale of MIG-29 jets.

The reporter did not identify the source of the threats, but Moscow, Ekho Moskvy, radio said he was being "intimidated" by federal security agents.

Kommersant said the deal also provided Damascus with short-range ballistic missiles. Safronov was also said to be probing the possible sale of surface-to-air missiles to Iran.

The paper said the transactions were to be routed through Belarus, so that Moscow could avoid accusations of supporting "pariah" states.

Russian arms sales to the Middle East have drawn sharp criticism from Israel and the United States, which accuse both Iran and Syria of attempts to destroy the Jewish state.

Russian police suggested Monday that Safronov's fall was either an accident or a suicide, after preliminarily ruling out any criminal activity. Prosecutors have opened an inquest.