Julian Assange, the founder of WikiLeaks, is an Australian passport holder [Reuters]

Australian police have begun investigating whether any of the country's laws were broken by the release of hundreds of thousands of US diplomatic cables by the whistleblowing website WikiLeaks, officials said.

"From Australia's point of view we think there are potentially a number of criminal laws that could have been breached by ... the release of this information," Robert McClelland, Australia's attorney-general, said on Monday.

"The Australian Federal Police are looking at that. Clearly, I don't want to pre-empt the outcome of that advice."

The communications between US missions abroad and the state department in Washington contain potentially embarrassing information for the US administration and other governments.  

The diplomatic cables, which are being released in batches over the coming days, include hundreds sent by US officials in Australia.

One of the dispatches describes Australia as a "rock-solid" ally. Others name Australians who have disappeared in the Middle East and then been added to "terrorist" watch lists. 

'Every assistance'

Julian Assange, the founder of WikiLeaks, is an Australian passport holder, but McClelland told reporters he was not aware of a US request to cancel the passport. 

"The United States authorities are looking at law enforcement actions as the lead country, and we are providing every assistance and could be expected to provide every assistance," he said.

McClelland said Australia would also support any legal action taken by the US as a result of its inquiries.

Assange's whereabouts are unclear, although he spoke to a conference in Jordan before the release on Sunday by a videolink.

Stephen Smith, Australia's defence minister, said later that a cross-government committee was studying the documents to ascertain what damage could be done by their release.

"We need to take it ... step by step, but our starting and endpoint is essentially protecting Australia's national interest," he said in an interview on Sky News television.

"This is an act which again one has no option but to absolutely condemn it. It potentially puts national security interests and it puts the safety and welfare of individuals at stake."

Before WikiLeaks released the more than 250,000 documents on Sunday, the US administration sought to ease the diplomatic fallout by calling a number of world leaders and sending ambassadors to brief a number of nation's foreign ministries.