Al Qaeda leader Osama bin Laden has apparently warned the American people against their government's close ties with Israel.

"The time has come for you to liberate yourselves from fear and the ideological terrorism of neo-conservatives and the Israeli lobby," an audio recording posted on an website said.

"The reason for our dispute with you is your support for your ally Israel, occupying our land in Palestine."

The 11-minute message was posted a few days after the eighth anniversary of the September 11, 2001, attacks.

The authenticity of the recording has not been verified but the website is often used by supporters of al Qaeda.

In the tape, the speaker said there had been no real change in US policy because President Barack Obama had retained people, like Defence Secretary Robert Gates, from former president George Bush's administration.

"If you think about your situation well, you will know that the White House is occupied by pressure groups," the recording said.

"Rather than fighting to liberate Iraq - as Bush claimed - it (the White House) should have been liberated."

Bin Laden, the leader of the group that mounted the September 11 attacks in the US is thought to be in hiding in the mountainous terrain along the Afghan-Pakistani border.

The attacks carried out by al Qaeda operatives in 2001 killed nearly 3,000 people.

The speaker also referred to US military actions in Afghanistan to support the Afghan government against the Taliban, allies of al Qaeda, and support for Pakistan, which faces militant violence.

"If you stop the war, then fine. Otherwise we will have no choice but to continue our war of attrition on every front," it said.

"You have only changed the faces in the White House," he said, referring to Mr Obama who took office this year.

"Obama is a weakened man. He will not be able to stop the war."