The US administration says the massive disclosure of documents could endanger US lives in Afghanistan.
But Paul Rogers, professor of peace studies at Bradford University in the UK, says it is unlikely the leak will affect operations in Afghanistan.
“It is embarrassing to the US but the reports as a whole demonstrate what many independent analysts have already concluded: the war in Afghanistan is unwinnable,” he says.
In one of the documents, Pakistan's former spy chief Hamid Gul is described at a January 2009 meeting with a group of insurgents following the death by CIA drone attack of a leader of Al-Qaeda operations in Pakistan.
Rogers says Pakistan is keen to maintain as much influence in Afghanistan as it can, “mainly because it fears Indian influence, and the best way for Pakistan to do this, is with traditional links to the Taliban and other paramilitary groups”.
According to The Guardian, the documents reveal hundreds of civilians were killed by coalition troops in unreported incidents as well as the existence of a covert unit to "kill or capture" Taliban leaders.
The source of leak is unknown.
US President Barack Obama has set a deadline of July 2011 as the start of a gradual drawdown of US troops, after a nine-year mission.