A Chinese bishop who has been under house arrest since rejecting the government's state-approved Catholic body has reportedly reversed his position in a shock turnaround.

Bishop of Shanghai, Thaddeus Ma Daqin, wrote in a blog post on June 12: "For a certain time, I have been deceived by others and [said and] made certain wrong words and deeds about the CPA [or CCPA, the Chinese Catholic Patriotic Association]."

Bishop Ma openly rejected the CCPA in 2012 during his consecration ceremony at St Ignatius Cathedral in Shanghai.

In front of 1,000 Catholics and government officials, he said it wouldn't be "convenient" for him to remain part of the state-approved organisation. Many people reportedly erupted into "thunderous applause", according to Reuters. Others wept.

Relations have historically been strained between the Catholic Church and China's ruling Communist party over irreconcilable claims to authority. The Vatican does not accept the validity of episcopal consecrations by the CCPA, and an underground Catholic Church refuses to compromise with the state and is loyal only to the Pope.

Bishop Ma accused the CCPA of defying the Vatican, and was immediately put under house arrest. He has since been banned from pastoral ministry, and was forced to attend communist indoctrination classes.

In 2014, a spokesman for the CCPA told Reuters: "He [Ma] deceived the bishops and cheated the government as well as the public. How can you then take on the responsibility for such a large diocese as Shanghai?

"This clearly shows that he was under the influence of foreigners."

According to UCA News, the suggestion that Ma may now have reversed his position on the CCPA has sent "shockwaves through the Catholic Church in China".

However, a source suggested to America magazine that it's possible the blog post was not actually written by Ma.

"One section of the text is 'rather rude' and quite unlike him," the magazine was told.