Assange has said he was abandoned by his country.
Attorney General Robert McClelland said Assange is "entitled" to return home. But he said Australia will investigate criminal matters because of agreements signed with other countries, the Australian Broadcasting Corp. reported Monday.
WikiLeaks last week released 250,000 classified U.S. State Department cables through selected news outlets, drawing sharp criticism from U.S. officials, some of whom said WikiLeaks' actions were criminal. Separately, Sweden has issued a warrant for Assange to question him on sexual assault claims made during the summer.
Interpol placed Assange on red-flag alert last week.
During the weekend, Assange indicated he would like to return to Australia but said McClelland had made it clear he could not return. McClelland said Assange could return home and obtain consular assistance overseas, the Australian broadcaster said.
Assange "is aware that Australia has obligations pursuant to agreements we have signed that ensure we will provide mutual assistance to countries investigating criminal law enforcement matters," McClelland said. "There is every prospect that national security-sensitive information will be published that will actually prejudice the safety of individuals."
Australia's federal police are investigating whether Assange committed any Australian crimes, McClelland said.