"During the past three months, I have been given a vast amount of relevant material by the Commonwealth and state departments and agencies with involvement in the matters under investigation and also by Haneef's representatives," Clarke said.

"A very high proportion of the material carries a security classification which limits the extent to which it can be shown to other people or disclosed generally," Clarke was quoted as saying by The Australian newspaper.

Clarke said he knew his decision "will cause a great deal of dissatisfaction, not least on the part of Haneef and his legal representatives, but my fundamental duty is to examine fully the matters covered by my terms of reference and to provide the government with a comprehensive report. The originating agency alone has the authority to remove the classification and the inquiry has not been given authority to publish the classified material."

Publishing some information without the agreement of UK authorities will seriously damage the international relationship between Australia and the UK, Clarke said. He said he will continue his inquiry as planned, but statements, transcripts of interviews and related documents will not be posted on the inquiry's web site.

"This I intend to do -- it will then be for the government to decide how and in what time frame to make its contents public and to act on my recommendations," Clarke added.

Haneef, who hails from Bangalore, was charged with recklessly helping a terrorist organisation after his SIM card was found with a cousin linked to the failed UK car bombings. Despite the charges being revoked, the Australian government revoked his work visa, forcing him to return to Bangalore. However, the judiciary quashed the government's directive and restored his visa.