Moreover, the average age of Christian congregations will have risen to 64 as the young abandon the churchgoing habits of older generations in the face of growing secularisation.

The total membership of all the denominations will fall from 9.4 per cent of the population to under five per cent by 2040, and 18,000 more churches will have closed, the report says.

The study paints a grim picture of a disestablished and demoralised Church of England struggling against the forces of secularism.

It foresees a nation in which faith schools have become multi-faith schools, Songs of Praise has been taken off the air, Alpha courses abandoned and Christmas rebranded as "Winterval".

The lifestyle of Christians will be no longer distinctly different from the rest of the population, "except in small sect-like groups that have retreated from society", says the report, The Future of the Church.

The seriousness of the crisis was acknowledged by the Bishop of Manchester, the Rt Rev Nigel McCulloch, who has been involved in previous Christian Research reports.

"It is no good Church leaders acting like company managers trying to present the statistics in the most favourable light," he said.

"The truth is stark. What these statistics need to do is to galvanise the Church into realising that it must communicate the gospel where people are or we will not deserve to have a Church."

The Bishop said the Church expended too much energy on relatively trivial matters. Too much time was spent on tasks such as reforming Synodical government or the liturgy, he said.

Peter Brierley, the executive director of Christian Research, said the study should act as a "wake-up call" to Church leaders.

"I hope that these findings concentrate minds in what is becoming a real crisis," said Dr Brierley, who has been collating Church figures for 40 years. "The story behind them is how few young people are being attracted to church."

He said the Churches had begun to tackle these issues with initiatives such as Fresh Expressions, which encourages new forms of alternative worship, but much more was needed. According to the report's projections, the proportion of the population describing itself as Christian in the national Census will have dropped from the 72 per cent recorded in 2001 to about 35 per cent in 2040.

Non-Christian religions, including Islam, will represent about 15 per cent of the population (up from six per cent in 2001), of whom about six per cent will be active worshippers.

All the main denominations, from the Church of England and the Roman Catholics to the Methodist and United Reformed Churches, are suffering from long-term decline, the figures show. The only groups to buck the trend are the non-white ethnic Churches.

END