Daniel Ellsberg, a former US military analyst, has described the disclosure of the Afghan war logs as on the scale of his leaking of the "Pentagon Papers" in 1971 revealing how the US public was misled about the Vietnam war.

"An outrageous escalation of the war is taking place," he said. "Look at these cables and see if they give anybody the occasion to say the answer is 'resources''. He added: "After $300bn and 10 years, the Taliban is stronger than they have ever been ... We are recruiting for them."

However, the equivalent of the Pentagon Papers on Afghanistan - top secret papers relating to policy - had yet to be leaked, he said.

People could read the logs to discover what they now need to ask, such as what their money was being spent on, he said. They would have an effect on public opinion, but the question, Ellsberg said, was how they would influence the US and UK governments.

He compared them to the document leaked in 2003 by the GCHQ officer, Katharine Gun, which revealed how the US asked Britain to spy on neutral countries at the UN before the invasion of Iraq. The disclosure influenced the attitude of the neutral countries who refused to vote for the invasion.