Wikileaks is about to drop its biggest-ever bombshell – some 2.7-million confidential diplomatic cables from US embassies around the world – and, although US credibility is likely to take the worst hit, much of the collateral damage may end up in Moscow.

"Among the countries whose politicians feature in the reports are Russia, Afghanistan, and former Soviet republics in Central Asia. But other reports also detail potentially embarrassing allegations reported to Washington from US diplomats in other regions, including East Asia and Europe," Reuters reported Thursday, noting that this huge document dump is expected as early as next week.

Dispatches sent by embassy workers often contain detailed accounts of private conversations with local politicians, businesspeople, journalists, dissidents, academics and public figures. The anticipated blizzard of dispatches from the US Embassy in Moscow to Washington is likely to publicly reveal the raw workings of US diplomacy on the ground and its range of contacts within Russian society. It may also detail the process by which the State Department forms its judgments about the Kremlin and its policies.

Some sensitive topics may include corruption among Russia's top politicians, details of political infighting, deeply critical views expressed to US diplomats by Russians in the opposition, as well as unflattering portraits of Kremlin leaders and their habits.

Russian diplomats contacted Friday said they don't expect the contents to be sensational or politically damaging to the Kremlin, but suggest that the breach of confidentiality might do untold damage to future US-Russian relations.

"As a diplomatic researcher, I must say that I'm really curious to see this material," says Yevgeny Bazhanov, deputy rector of the Russian Foreign Ministry's Diplomatic Academy, which trains Russian diplomats.

"But it will undoubtedly hurt the relationship. It's not that we'll find out that our American colleagues were critical of us in their dispatches – we know that already – but that all these raw materials, including frank private conversations, will spill into the open. How can we talk candidly with our American colleagues in future if we don't know who's going to read it tomorrow?"

Wikileaks previous releases of massive troves of secret US documents from the wars in Iraq and Afghanistan were intensively covered in the Western media, and got front-page attention in Russia as well.

Thanks to the Kremlin's near-total stranglehold on Russia's major media outlets, that is not likely to happen if the next round of revelations proves to be embarrassing to Russia.

But Russia's former ambassador to Belgium, Dmitry Ryurikov, says it is nevertheless going to roil the diplomatic waters, perhaps for years to come.

"This is a ticklish issue, and it might cause damage to relations, scandal, refutations, and even lead to lawsuits," he says. "There are some documents that are not meant to be made public; that is a matter of strict confidentiality and ethics. One group of people might read them and say, 'We told you that [the Americans] can not be trusted,' and another group might say, 'we always knew that these people [who talk privately with US diplomats] are rascals who are ready to sell out' their country," he says.

Some Russian politicians and anti-Kremlin activists may have reasons to fear seeing their private conversations with US diplomats being splashed all over cyberspace, say experts.

"Diplomats talk to people and send cables home, that's what they do," says Alexander Konovalov, president of the independent Institute for Strategic Assessments in Moscow. "Sometimes they report on a single conversation, sometimes they describe aggregated discussions. But I think even with no names, it will be possible [for Russian security agencies] to trace a person they have talked to. In our country, such a person may well face accusations and moral condemnations."

Hearsay, misinterpretation

The damage will be done even if the contents of a particular cable are based on hearsay or misinterpretation on the part of the diplomat who wrote it, Mr. Ryurikov says.

"Once I had a chance to have a look at a report of one European diplomat about a private conversation we'd had," he says. "I was surprised to see that it was distorted. I happened to meet him a couple of years later, and conveyed my feelings to him. He blushed and said it was his ambassador who made some corrections for some reasons of his own.... These things are always very delicate and potentially explosive."

State Department spokesman Philip Crowley told journalists Thursday that the US government has long known that Wikileaks is in possession of secret diplomatic cables, and is bracing itself for a storm.

"We are gearing up for the worst-case scenario, that leaked cables will touch on a wide range of issues and countries," he said.

"We are in touch with our posts around the world. They have begun the process of informing governments that a release of documents is possible in the near future.... These revelations are going to create tensions on our relationships between our diplomats and our friends around the world," Mr. Crowley added.

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