Washington, Nov 29 (DPA) The White House called the unauthorised release Sunday of hundreds of thousands of classified US documents by the self-styled whistleblower website WikiLeaks "reckless" and "dangerous".

The publication of the documents could endanger the lives of human rights activists, dissidents and opposition leaders around the world who regularly speak to US officials, White House spokesman Robert Gibbs said.

"WikiLeaks has put at risk not only the cause of human rights but also the lives and work of these individuals," Gibbs said.

"President (Barack) Obama supports responsible, accountable, and open government at home and around the world, but this reckless and dangerous action runs counter to that goal," he added.

The State Department has been reaching out to governments around the world in the days leading up to the release of communications between headquarters in Washington and embassies and consulates in some 270 countries. US officials are worried that unflattering assessments of leaders in the documents could undermine relations.

"By its very nature, field reporting to Washington is candid and often incomplete information," Gibbs said. "It is not an expression of policy, nor does it always shape final policy decisions."

"Nevertheless, these cables could compromise private discussions with foreign governments and opposition leaders, and when the substance of private conversations is printed on the front pages of newspapers across the world, it can deeply impact not only US foreign policy interests but those of our allies and friends around the world," Gibbs added.