Although the governing Communist Party requires its 85 million members to be atheist, its leaders have lauded some aspects of religious life for instilling morality in the broader population and have issued directives ratcheting back the hard-line attacks on religion that characterized the Mao era.

Over the past decades this has permitted a striking religious renaissance in China, including a construction boom in temples, mosques and churches. Christianity is widely considered the fastest-growing faith; there are as many as 67 million adherents now, at least half of whom worship in unregistered churches that have proliferated across China, sometimes called underground or house churches.

The new regulations are more explicit about the party’s longstanding requirement that all religious groups register with the government, and the most vocal opposition so far has come from Protestant leaders unwilling to do so.

“These regulations effectively push house churches into taking on an illegal character,” said Yang Xingquan, a lawyer who is one of the signatories of the public statement. “This is very clear.”

Many Christians contend that government-approved churches are tools of the state, as sermons are vetted to avoid contentious political and social issues and clergy are appointed by the party rather than congregants or, in the case of the Catholic Church, the Vatican.