BBC religious affairs reporter
Tension between China and the Vatican looks set to escalate after the state-controlled Catholic church appointed another bishop without approval of the Holy See.
China has one of the fastest-growing Catholic communities in the world
Bishop Zhan Silu, 45, was installed as head of Mindong Diocese in eastern China's Fujian province during a ceremony held by the Chinese Patriotic Church on Sunday.
But the appointment was made without the blessing of Pope Benedict XVI.
Earlier this month, the Vatican reacted angrily to the appointment of two other bishops by the state-controlled Patriotic Church.
China has both a state-run Catholic association and an underground church which is loyal to the Vatican.
Lui Xinhong and Ma Yinglin may not be household names outside China but their consecration has cast a shadow over fragile talks to re-establish links between the Vatican and China which were severed over half a century ago.
The talks had been progressing well. The Vatican had even indicated it was prepared to break off ties with Taiwan, viewed by Beijing as a breakaway province
But the appointments of Xinhong and Yinglin appear to have ended that process.
In a strongly-worded statement, Pope Benedict XVI accused the Chinese of a "grave violation of religious freedom" and promptly excommunicated the two clerics.
However, the excommunication order could be suspended if it is proven that the two men were subjected to threats and pressure.
The installation of Zhan Silu, who celebrated his first full mass at Ningde cathedral on Sunday, looks set to further strain relations.
Just days before his appointment, Zhan Silu said he had written to the Vatican "to ask for recognition" but had never received a response.
The Chinese government does not recognise the Vatican's power to appoint bishops, but over the past five years, has allowed bishops to seek approval from the Holy See.
Last week, Chinese foreign ministry spokesperson Liu Jianchao warned the Vatican "not to interfere in China's internal affairs, including interfering in the name of religion".
It is difficult to ascertain how many Roman Catholics there are in China.
There are an estimated 10 million, divided between the officially-tolerated Patriotic Church, and an underground church which remains in communion with Rome.
For the Vatican, a resumption of diplomatic relations with China could be the gateway to controlling one of the fastest-growing Catholic communities in the world.
The Chinese want to improve ties with one of their biggest critics on the issue of religious freedom.
But why has the row erupted now?
It could be that this is the latest move by the Chinese in a complex game of diplomatic chess.
Father Jeroom Heyndrickx is director of the Verbiest Institute at Louvain University in Belgium.
A frequent visitor to China, he is surprised by the recent row, describing it as "a pity, because there was a kind of peaceful evolution going on, with the (Chinese) authorities closing one eye to approval from Rome".
So what will happen next? It is an issue that is unlikely to disappear.
Speaking to Italian radio, Cardinal Zen, the man considered to have the inside track on talks between China and the Vatican, said: "We cannot continue talking and pretending that nothing has happened. This matter is too serious. "
But China faces a problem.
About 40 Chinese Catholic dioceses are vacant at the moment. The Vatican prefers them to remain that way rather than be occupied by bishops who are not in communion with Rome.
Unless both sides can resolve this issue, any talks that may take place are likely to be fruitless.