A leading Anglican bishop has warned that the Church of England could become a minority sect within "a generation".
The Bishop of Manchester, the Right Rev Nigel McCulloch, said that the established Church is in danger of completely disappearing.
Bishop McCulloch said the clergy were being diverted from their true mission of evangelism by the debate over sexuality, 25 years of Church legislation and more red tape caused by secular regulations.
Figures published in The UK Christian Handbook: Religious Trends show that, at the current rate of decline, total Church membership will have fallen to 5,598,000 by 2005, down by more than a million people in 15 years. Over the same period, the number of church buildings will have fallen by 1,400 to 48,600 and the number of ministers by 1,000 to 35,400.
Even if there is no further decline, by the turn of the next century, there will still be thousands of churches and ministers, but they will have no Christians to minister to.
The waning interest in organised Christianity contrasts with the findings of the 2001 census, which included a voluntary question about religion for the first time. In response, 72% of the population said they were Christians. The Handbook acknowledges a "yawning gap" between what people say and church attendance.
Writing the forward to the Handbook, published by Christian Research, Bishop McCulloch said: "The overall picture presented by this book serves to highlight the dilemma which Christian churches in the United Kingdom currently face.
"It has long been said that there is a yearning for spirituality across our countries, but until now the evidence has been largely anecdotal."
Bishop McCulloch is not the first senior cleric to voice such concerns. In September 2001, the Archbishop of Westminster, Cardinal Cormac Murphy-O'Connor, caused dismay in ecclesiastical circles when he said Christianity in Britain had been all but vanquished.
He blamed the rising secular interests of British society for the inevitable decline of the religious doctrine.