China has launched an investigation into the use of imported textbooks at its universities, government websites and an official said on Tuesday, after its education minister called for "Western values" to be banned.
China's education ministry has asked universities nationwide to fill out questionnaires detailing their use of "foreign" classroom materials, according to a copy posted on a government website.
The education department of the eastern province of Anhui posted the 13-question survey on its website, but deleted it after an official surnamed Peng confirmed to AFP it had been sent to colleges.
The survey probes the extent to which foreign textbooks are used, how they are acquired and how universities manage their use.
News of the inquiry comes weeks after state media quoted China's education minister Yuan Guiren saying: "Never let textbooks promoting Western values appear in our classes."
The ruling Communist party often brands concepts such as multiparty elections and the separation of powers as "Western", despite their global appeal and application.
Yuan's comments were seen as the latest sign of ideological tightening under President Xi Jinping.
"Remarks that slander the leadership of the Communist Party of China" and "smear socialism" must never appear in college classrooms, Yuan added, according to the official Xinhua news agency.
China's universities are run by the Communist party, which tightly controls discussions of history and other topics it construes as a potential threat to its grip on power.
But translations of textbooks by foreign academics are widely used in Chinese universities in a variety of fields, especially the sciences.
China has tightened controls on academics since Xi assumed the party leadership in 2012, with several outspoken professors sacked or jailed.
The Beijing Youth Daily reported that the survey was sent to almost all the country's universities, including all of China's top-ranked colleges.
Posts on two universities' websites indicated that the survey was sent out earlier this month. The education ministry could not immediately be reached for comment.
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 daughter, who reportedly attended Harvard.