Wikileaks is set to make public classified US documents said to contain information so embarrassing the States has briefed Australia, Britain and Canada to expect some shocks.

Whistleblower website WikiLeaks claims it will be posting 2.8 million secret documents, which it says will redefine global history.

The documents are said to contain the US’ blunt appraisal of foreign powers and could be diplomatically devastating, possibly threatening long-standing alliances.

A US State Department spokesman said Wednesday Wikileaks’ release of the confidential documents would damage trust in the United States as a diplomatic partner.

“These revelations are harmful to the United States and our interests,” he said.

“They are going to create tension in relationships between our diplomats and our friends around the world.

“We wish this would not happen, but we are obviously prepared for the possibility that it will.”

Wikileaks, founded by Julian Assange, has previously released tens of thousands of American classified documents about the wars in Iraq and Afghanistan.

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