VATICAN CITY - Pope Benedict XVI invited all Roman Catholics in China to unite under his jurisdiction Saturday and urged Beijing to restore diplomatic ties and permit religious freedom.

He called the state-run Catholic Church "incompatible" with Catholic doctrine but nevertheless made unprecedented overtures toward it.

China forced its Roman Catholics to cut ties with the Vatican in 1951, shortly after the officially atheist Communist Party took power. Worship is allowed only in the government-controlled churches, which recognize the pope as a spiritual leader but appoint their own priests and bishops.

Millions of Chinese, however, belong to unofficial congregations that remained loyal to Rome.

In an eagerly awaited 55-page letter to the faithful in China, Benedict insisted Saturday on his right to appoint bishops, but said he trusted that an agreement could be reached with the Beijing authorities on nominations.

Significantly, Benedict revoked previous Vatican-issued restrictions on contacts with the clergy of the official church, and in fact recognized that some Chinese faithful have no choice but to attend officially recognized Masses.

The Vatican said in a note that accompanied the letter that it was prepared to move its diplomatic representation from Taiwan to Beijing "at any time" as soon as an agreement with the government was reached.

The letter -- translated into Mandarin and Cantonese and posted on the Vatican's website -- marked the most significant effort by Benedict to balance his pastoral concerns for the up to 12 million Roman Catholics in China who are divided between an official church, the Chinese Patriotic Catholic Association, and an underground church that is not registered with the authorities.

Benedict praised those Catholics who resisted pressure to join the official church and paid a price for it "with the shedding of their blood." But he urged them to forgive and reconcile with others for the sake of unifying the church.

"Indeed, the purification of memory, the pardoning of wrongdoers, the forgetting of injustices suffered and the loving restoration to serenity of troubled hearts ... can require moving beyond personal positions or viewpoints, born of painful or difficult experiences," he wrote.

Tellingly, Benedict referred repeatedly to the "Catholic Church in China," without distinguishing between the divisions -- an indication of his aim to see the two united and in communion with Rome.

But on several occasions, he also called the Patriotic Association "incompatible with Catholic doctrine" because it named its own bishops and sought to guide the life of the church.

At the same time, however, Benedict made an unprecedented gesture: He revoked 1988 guidelines issued by the Vatican's evangelization office that sought to limit contacts with the official church and declared that any bishop ordained by the official church would incur an automatic excommunication.

Vatican analysts have said that a revocation of the 1988 guidelines would represent a clear indication of the pope's desire to move beyond the conflicts of the past in a bid to bring all Chinese Catholics under Rome's wing.

The letter does cite the canon law which provides for excommunication for an illicitly ordained bishop, but Benedict also welcomed the fact that most bishops in the official church had now reconciled with the Holy See and that only a few remain "illegitimate."

The Vatican spokesman, the Rev. Federico Lombardi, said the revocation of the 1988 norms was "significant."

"It means, that today the Church in China can and must follow the norms that are common in the universal church," he said.

In a message directed to the Beijing authorities, Benedict insisted that the Church had no political aims in China. At the same time, however, he said the state cannot interfere "in matters regarding the faith and discipline of the church."

"It is likewise clear that she (the church) asks the state to guarantee to those same Catholic citizens the full exercise of their faith, with respect for authentic religious freedom," he wrote.

Benedict stressed that he alone must appoint bishops to ensure apostolic succession. But he said he was willing to compromise.

"I trust that an accord can be reached with the government so as to resolve certain questions regarding the choice of candidates for the episcopate," he wrote.

The Vatican would like to have a formula as they have with Vietnam, another communist country, whereby the Vatican proposes a few names and the government selects one.