The US ambassador to Australia Jeff Bleich has criticised the Rudd government's plan to filter the internet, saying the same goals can be achieved without censorship.

The federal government's $128.8 million Cyber Safety policy includes forcing ISPs to block access to certain websites and blacklist offensive material. Legislation to enable the scheme is set to be introduced this year.

"Internet has to be free" ... US Ambassador to Australia Jeff Bleich

On ABC's Q&A program last night, Mr Bleich said the "internet has to be free" and that there were other means of combating nasty content such as child pornography.

"We have been able to accomplish the goals that Australia has described, which is to capture and prosecute child pornographers ... without having to use internet filters," he said.