Australian Prime Minister Julia Gillard has renewed her backing for a controversial Internet filter, saying it was driven by a "moral question".

Australian Prime Minister Julia Gillard Tuesday renewed her backing for a controversial Internet filter, saying it was driven by a "moral question".

The proposed filter will block access to material such as rape, drug use, bestiality and child sex abuse, and will be administered by Internet Service Provider companies.

However, web giants like Google, Yahoo! and Microsoft have slammed the initiative as setting a precedent for censorship, while cyber-activists have hit government websites with a targeted hacking campaign.

"My fundamental outlook is this: it is unlawful for me as an adult to go to a cinema and watch certain sorts of content, it's unlawful and we believe it to be wrong," Gillard said in a press club address.

"If we accept that then it seems to me that the moral question is not changed by the medium that the images come through."

The plan, which has also drawn concern from the US State Department, was put on hold pending a content review in July as national elections loomed.

Angry user groups have launched an online campaign accusing the government of censorship, likening the proposed system to firewalls operating in China and Iran.

Concerns have also been raised about the filter's impact on Internet speeds and the methods through which restricted content would be determined.

Gillard said how to set up the filter "is more complicated, but the underpinning moral question is, I think, exactly the same".

A review of what material should be excluded by the filter is expected to take at least 12 months.

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(c) 2010 AFP