A single delegation of Chinese pilgrims attending the Catholic Church's World Youth Day in Cologne, Germany, last week marked the latest breakthrough in relations between the Vatican and Beijing. The delegation included both "underground" Catholics long persecuted by communist authorities, as well as the official Chinese "patriotic" church that pledges loyalty to the Communist Party instead of Rome. Both the Vatican and Beijing have said little publicly about their differences. Instead, they have let a series of high-profile public events since Pope Benedict XVI began his pontificate in April signal tacit approval of a rapprochement. The delegation at World Youth Day, for example, traveled together. Created by the Chinese authorities in 1957 the Chinese Catholic Patriotic Association was an attempt to set up a national church outside Vatican authority. A separate underground Catholic Church nevertheless survived years of persecution and today it has an estimated 8 million followers -- double the number of faithful in its government-approved rival. On Aug. 3, shortly before World Youth Day, Benedict received 22 priests from the official church at the end of his Wednesday public audience. They had been to a two-week course at a Benedictine Abbey in Bavaria, the pope's homeland, and were on their way home. Observers said the meeting with the pope was a last-minute addition to the schedule, and would almost certainly have had official approval. There are clear indications that the rapprochement between the two churches has the Vatican's tacit approval as well as Beijing's backing. On June 28, Bishop Joseph Xing Wenzhi, a 42-year-old Chinese priest who had studied in the United States, was ordained as auxiliary bishop of Shanghai with two bishops attending -- one from each rival church. Bishop Joseph Fan Zhongliang, long-time leader of the Shanghai underground church, joined the government-approved bishop of Shanghai, Aloysius Jin Luxian for the ceremony. Both are Jesuits. Rome's approval was not made public, but a statement from the New York-based Maryknoll Fathers and Brothers, whose superior general attended the ceremony, said Bishop Wenzhi was ordained "with the approval of the Holy See and is duly recognized by the local government authorities responsible for religious affairs in China." The pressure on underground Catholics, particularly the aging generation of key senior prelates, has not stopped altogether. According to AsiaNews, Archbishop Anthony Li Duan, 78, for example, still "often undergoes checks and interrogations, as well as long periods of surveillance." Officially, the Vatican is in no rush to exchange ambassadors.