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The Vatican has threatened a Chinese priest with excommunication if China moves ahead with his government-backed bishop ordination, which has not been approved by the Holy See.

The Chinese government-backed appointment of the Rev. Yue Fusheng in northern Chinese city of Harbin on Friday is aggravating already-tense relations between the Vatican and the Chinese government.

In its statement on Wednesday Vatican asserted that the Rev. Yue Fusheng is aware that his ordination was not approved by the pope and thus "unlawful" and "illegitimate." The punishment for unlawful ordination is excommunication, according to the Vatican's Code of Cannon Law.

The statement also warned that the Chinese government-backed appointment was an infringement on religious freedom and would "create confusion and divisions among the Catholic community in China."

A spokesperson for the State Administration for Religious Affairs in China responded that the Vatican's public threats and accusations were "outrageous and shocking," restrictive of freedom, and detrimental to the development of the Chinese and universal Catholic Church.

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Since its formation over 60 years ago the Communist Party of China has mandated that religions only operate under government control, subsequently cutting ties with the Vatican, expelling foreign clergy, and creating the state-funded Chinese Patriotic Catholic Association (CPA). The refusal of the CPA and the Holy See to recognize each other's authority has created points of contention between the two, particularly over the installation of bishops without papal approval as well as the issues of abortion and contraception.

While the CPA is the only legal Catholic organization in China, millions of Chinese Vatican loyalists continue to worship in "underground" churches.

Catholicism has existed in China for over eight centuries. While the Chinese government reports that the country has 5.7 million Catholics, unofficial estimates range from 12 million to over 60 million.