The National Secular Society will claim in its study on Monday that the Prince of Wales' coronation will provide an "opportune moment" to make the case for separating the Church of England with the state - or "disestablishment."
The report, called 'Separating Church and State: The Case for Disestablishment', outlines the central arguments for splitting the church and state and considers the challenges involved in making this a reality.
It also highlights the fact that only 25 per cent of countries had a state religion in 2011 and, of those, a minority were classed as liberal democracies.
Currently, the reigning monarch is head of state, the head of the Church and holds the titles of supreme governor of the Church of England and defender of the faith.
The report explains that since the mid-nineteenth century, the process of reducing the powers of the Church has stalled, with the only substantive change being the Church of England Assembly (Powers) Act in 1919.
This amendment granted the Church additional powers over its own governance, enabling it - through the Synod, to bring forth its own legislation, and even to amend Acts of Parliament on matters affecting it.
The report says overt support for the church's establishment "remains weak" but acknowledges "no clamour" for disestablishment among politicians and that most members of the general public are "simply indifferent to the issue".
The study concludes: "The voices of religious privilege are loud and their vested interests are strong.
"But if the problems of the 21st century life are to be effectively addressed, and if Britain is to become a modern state rather than one in which parliament continues to cleave to its medieval past, then the separation of church and state needs to be part of the solution."
