China's education minister has vowed to ban university textbooks which promote "Western values", state media said, in the latest sign of ideological tightening under President Xi Jinping.

"Never let textbooks promoting Western values appear in our classes," minister Yuan Guiren said, according to a report late Thursday by China's official Xinhua news agency.

"Remarks that slander the leadership of the Communist Party of China" and "smear socialism" must never appear in college classrooms, he added.

China's universities are run by the ruling Communist party, which tightly controls discussions of history and other topics it construes as a potential threat to its grip on power.

The party often brands concepts such as multiparty elections and the separation of powers as "Western", despite their global appeal and application.

Beijing and Hong Kong authorities blamed recent student-led demonstrations in Hong Kong calling for greater democracy in the former British colony on "foreign forces", although no evidence has been cited.

China has tightened controls on academics since Xi assumed the party leadership in 2012, with several outspoken professors sacked or jailed.

Xia Yeliang, an economics professor at the prestigious Peking University, was fired from his post in 2013 after a 13-year tenure in a decision he attributed to persistent calls for political change in China.

Xia was one of the original signatories of the reformist petition Charter 08, whose main author Liu Xiaobo remains in prison even after winning the Nobel Peace Prize.

The university attributed the dismissal to poor teaching, and he moved to the US last year.

The minister's remarks came shortly after Xi called for authorities to increase the party's leadership of universities, and to "strengthen and improve ideological work".

"We should never allow teachers to complain or vent grievances in the classroom, so as not to transfer negative emotions to the students," Yuan said according to Xinhua.

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Teachers must adhere to the "political, legal and moral bottom line," Yuan added, using a common expression for support of China's authoritarian political system.

He also suggested Xi's own speeches -- recently officially published in book form -- should "enter teaching materials, enter the classroom and enter the minds" of students.

China has greatly expanded its higher education system as its economy has grown, with the total number of universities and colleges more than doubling in the past decade.

But many children of the country's political and business elite prefer to study at institutions in the US and Europe, including Xi's own daughter, who has reportedly attended Harvard University since 2010.

- 'Brainwashing' -

Most of the Tiananmen Square protesters in 1989 were students from Beijing universities and their demands included increased funding for education and a free press, both firmly under government control today.

Commentators on Chinese social media site likened Yuan's ideas to "brainwashing" and China's dark past, when teachers and intellectuals were paraded through the streets as enemies of the revolution.

"I guess these commands are more strict than those during the Cultural Revolution," said one user on Sina Weibo, a Twitter-like service, referring to the decade of chaos under Mao Zedong when nearly all schools were shuttered.

"Finally, there will be nothing keeping me awake in class, I can sleep all day," another user wrote.

Many of China's current leaders, including Yuan, were forced to postpone higher education for the turbulent years of the Cultural Revolution, when Communist orthodoxy was the most important lesson.

Analysts say this may incline them against change in a range of areas, including education, media and Party ideology.

A Chinese province last month announced plans to install CCTV cameras in university classrooms, sparking an outcry from lawyers who say the move would further curb academic freedom.

Authorities have in the past installed video equipment in the classrooms of outspoken academics, most notably Uighur economics professor Ilham Tohti, who was sentenced to life in prison for separatism in September.

Evidence from the classroom cameras was used to convict the scholar, in a case that was condemned by human rights groups.