Australia's education minister has urged universities to maintain academic integrity after a diplomat renewed a discussion about possible Chinese influence on campuses.
Frances Adamson, Australia's chief foreign affairs bureaucrat, called for debate not to be stifled in classrooms.
It follows recent claims of embassy influence on campuses - dismissed as "smear" by Chinese diplomats in June.
Education Minister Simon Birmingham said students should think critically.
"Universities need to be as ever vigilant today as they have been through their history in terms of ensuring their integrity, their high standing, their delivery of quality education and I am confident that they are doing that, they are challenging the students who come to them, whatever the background of those students," he told the Australian Broadcasting Corporation.
Mr Birmingham did not directly reference China, but his comments were in response to a speech by Ms Adamson at the University of Adelaide's Confucius Institute on Sunday.
Why Australian universities have upset Chinese students
Ms Adamson, the Department of Foreign Affairs and Trade secretary, directly addressed "international students" during her lecture called Australia and China in the 21st Century.
"No doubt there will be times when you encounter things which to you are unusual, unsettling or perhaps seem plain wrong," she said.
"So when you do, let me encourage you not to silently withdraw, or blindly condemn, but to respectfully engage. The silencing of anyone in our society - from students to lecturers to politicians - is an affront to our values."
Sensitive topic
Ms Adamson, a former Australian ambassador to China, said universities must remain "secure and resilient" when "exposed to unexpected pressure".
"As China becomes more important to Australia's future and that of the world, it follows that there will be more scrutiny of China, including the way it seeks to exercise influence internationally," she said.
In some prominent cases in recent months, Chinese students at Australian universities have complained about teaching materials being incorrect or insulting to China. One incident involved the listing of Taiwan and Hong Kong as countries.
In June, Australian media outlets reported that the Chinese embassy in Australia had "orchestrated" Chinese student organisations to hold a rally welcoming China's Premier Li Keqiang.
The reports also claimed that Chinese students in Australia were being monitored for dissident behaviour.
Chinese students make up more than a quarter of Australia's international students.
Photo copyright: GETTY IMAGES (Caption: There has been debate over freedom of discussion at Australian universities)