A new book critical of the Chinese government’s influence in Australia won’t make it to shelves for the time being–because, says the author, of the Chinese government’s influence in Australia.

Clive Hamilton, professor of public ethics at Charles Sturt University, was set to publish his book, Silent Invasion: How China is Turning Australia into a Puppet State, in April 2018. But on Nov. 8 his publisher, Sydney-based Allen & Unwin, said it was concerned about a possible defamation suit and wanted to delay the book.

According to the email from Allen & Unwin to Hamilton, obtained by the Australian Broadcasting Corporation (ABC), the publisher was afraid of recourse from China:

The publisher said it was concerned about “potential threats to the book and the company from possible action by Beijing”. In the email the company explained: “The most serious of these threats was the very high chance of a vexatious defamation action against Allen & Unwin, and possibly against you personally as well.”

Hamilton didn’t want to postpone the publication of Silent Invasion, and decided to part ways with Allen & Unwin on the book. ”What we’re seeing … is the first instance where a major Western publisher has decided to censor material of the Chinese Communist Party in its home country,” he told ABC. Hamilton, who has previously published more than five books for Allen & Unwin, tweeted that he is looking for a new publisher.

Earlier this month global scientific publisher Springer Nature, which publishes Scientific American, said it agreed to block access to certain articles in China at the request of the Chinese government. The company removed more than 1,000 articles on Taiwan, Tibet, the cultural revolution, and other politically sensitive topics in China. In August, Cambridge University Press pulled 300 similarly “sensitive” articles from its China site, but then reversed its decision in response to criticism.

Hamilton, Allen & Unwin, and China’s state council information office have not responded to requests for comment.