HBO website and comedian John Oliver censored in China

Chinese authorities blocked HBO's website in China, just days after Oliver took Xi to task, anti-censorship and monitoring group GreatFire.org said on Saturday.

HBO joins a long list of Western media outlets that have had their websites blocked in China including The New York Times, Facebook, and Twitter.

"China: the country responsible for huge technological advances but it still can't seem to get pandas to f***," Oliver opened the episode of "Last Week Tonight" that is causing the problems.

Those technological advances include draconian surveillance and censorship measures which appear to have made HBO and Oliver their latest victims.

Oliver's name and that of the show he hosts were censored on China's popular twitter like Weibo.

"Send failure" Weibo returned when AFP attempted to post Oliver's name.

"Content is illegal!" the service said.

YouTube, which also airs "Last Week Tonight", has long been blocked in China.

Oliver's segment dug into Xi's distaste at comparisons to the self-described "bear of very little brain" and introduced viewers to repressive changes underway in the world's most populous country.

Chinese netizens have often compared Xi to A.A. Milne's most famous creation, something that censors have been quick to purge inside the Great Firewall.

The segment also recounted recent headlines: from Xi becoming "emperor for life" to a corruption purge that targeted his political rivals, to a crackdown on freedom of expression, human rights, and religion, to an ongoing suppression and imprisonment campaign against China's Uighur ethnic minority.

"Xi is actively removing the post-Mao guardrails that were put in place," Oliver said of changes to China's constitution which allow him to remain in power indefinitely.

"China is becoming more authoritarian just as it has major plans for expansion onto the world stage," Oliver said as the segment neared an end.

"The era of do as we say may be dawning."