The Chinese government has banned George Orwell's dystopian satirical novella Animal Farm and the letter 'N' in a wide-ranging online censorship crackdown.

Experts believe the increased levels of suppression - which come just days after the Chinese Communist Party announced presidential term limits would be abolished - are a sign Xi Jinping hopes to become a dictator for life.

The China Digital Times, a California-based site covering Chinainfo-icon, reports a list of terms excised from Chinese websites by government censors includes the letter 'N', Orwell's novels Animal Farm and 1984, and the phrase 'Xi Zedong'.

The latter is a combination of President Xi and former chairman Mao Zedong's names.

Search terms blocked on Sino Weibo, a microblogging site which is China's equivalent of Twitterinfo-icon, include "disagree", "personality cult", "lifelong", "immortality", "emigrate", and "shameless".

It was not immediately obvious why the ostensibly harmless letter 'N' had been banned, but some speculated it may either be being used or interpreted as a sign of dissent.

The move to lift limits on the length of time leaders can stay in post has been met with global condemnation and a widespread backlash in China since it was announced on Sunday on the eve of an annual political congress in Beijing.

The proposed amendments to China's constitution are expected to be rubber-stamped by the country's parliament, the National People's Congress, which begins its annual meeting on Sunday.

China has a stringent policy of internetinfo-icon censorship because authorities view foreign websites and social mediainfo-icon as a threat to national security.

This censorship is fortified by the Great Firewall of China - a term which refers to the combined force of technological and legislative measures which tightly control the internet on the mainland.

Facebookinfo-icon, Twitter and YouTube have long been blocked in the country and even Winnie the Pooh recently found himself subject to China's latest internet crackdown.

In July, references to the cartoon bear on Sina Weibo were removed after his image was compared to President Xi.