Last night, identically worded statements were issued by Lambeth Palace, on behalf of the Archbishop of Canterbury, and Buckingham Palace, saying: 'Details about the Coronation service will be released in due course.'

The tensions have arisen nearly 30 years after Charles famously declared his wish to be 'Defender of Faith', not simply 'Defender of the Faith' – a title that all English sovereigns since Henry VIII have held as head of the Church of England.

Statements were issued by Lambeth Palace, on behalf of the Archbishop of Canterbury (right), and Buckingham Palace, saying: 'Details about the Coronation service will be released in due course'.

It is already expected that the Coronation will be more religiously and culturally diverse than the late Queen's 1953 service.

But The Mail on Sunday has been told that Church leaders are resisting a more active role for other faith leaders, given that it is an Anglican ceremony, as well as a constitutional event.

A compromise option could be for the King to hold a separate ceremony at which other faith leaders would play an active role.

In a joint message last month, Justin Welby, the Archbishop of Canterbury, who will officiate at the ceremony, and Archbishop of York Stephen Cottrell said the Coronation 'at its centre is a Christian service… rooted in long-standing tradition and Christian symbolism'.

According to a source, a meeting held at Lambeth Palace last month heard that the drafting of the order of service was led by Archbishop Welby and 'conducted with scrupulous regard for the range of opinion among Anglican clergy'.

The meeting was told that 'the current aim' was to publish it 'before Easter, with suitable guidance for the clergy'.

The Archbishop is also understood to be giving the King 'religious guidance' on the significance of his oath, the commitments he will make to his subjects and the Christian symbolism of the regalia.

Religious affairs commentator Catherine Pepinster claims today she has been told that this wrangle has delayed the release of the Coronation's Order of Service.

The dispute emerged just days after the Church Times reported that Manchester Cathedral had apologised for permitting the Muslim call to prayer to be recited inside the cathedral itself last month, rather than in a separate room allocated for prayer.

The King, as Supreme Governor of the Church of England, is required by the Bill of Rights Act 1688, modified by the Accession Declaration Act of 1910, to declare at either his Coronation or at the first State Opening of Parliament that he is a 'faithful Protestant' and will 'secure the Protestant succession'.

In addition, the Coronation Oath Act of 1688 requires the King to declare he will maintain the established Anglican Protestant Church.

One source said Church laws meant that the participation of non-Christian faith leaders should be restricted to them just being present in Westminster Abbey and taking part in the procession.

Ms Pepinster, writing in today's Mail on Sunday, says the King is still wrestling with how to ensure that his new role accords with his realm's many non-Christian faiths.

Church sources say the monarch has been told that his desire for a 'diverse' ceremony, including participation by non-Christians, risks clashing with centuries- old canon law. Pictured at the West London Synagogue

She adds: 'Is it wise for the Christianity of the Coronation – an ancient ceremony dating back more than 1,000 years – to be diluted so that, in the name of diversity, other faiths are included?

'Anglican canon law effectively rules out representatives of other faiths being actively involved in services if those faiths do not accept the Holy Trinity of Christian doctrine – the Father, Son and Holy Ghost.

'These grave tensions between modernisation and tradition explain why the Coronation order of service has still not been made public.'

In 2015, Charles made clear he saw no contradiction between being Defender of the Faith and 'protector' of other faiths, saying he minded 'about the inclusion of other people's faiths and their freedom to worship in this country'.

He said the late Queen had declared that the monarch's role was not to defend Anglicanism to the exclusion of other religions.

And in his speech to the nation and the Commonwealth the day after his mother's death last year, Charles also underlined his commitment to the Church of England – 'the Church in which my own faith is so deeply rooted'.

Gavin Ashenden, a former Chaplain to the Queen, last night warned the King against seeking any fundamental changes to the Christian Coronation. Dr Ashenden, who has become a Roman Catholic, said: 'This is a crisis long in the making but entirely predictable given the King's previous declarations.

'Charles's desire to reach out to other faiths is commendable and understandable, and it is only right that they are able to attend the Coronation. But any attempt to alter fundamentally the nature of the Coronation – a Christian ceremony in a 1,000-year-old abbey – would be entirely wrong and misguided. The King derives his authority and position from being a Christian monarch in keeping with the history of this country.'

Last night other faith leaders were relaxed about the Christian nature of the ceremony. Sir Iqbal Sacranie, the former founding Secretary-General of the Muslim Council of Britain, said: 'It is appropriate the formal ritualistic prayers of the Coronation ought to be Anglican as the King is from the Anglican faith.

'But the presence of other faith leaders will signify the importance that the King represents all the faith communities in the Kingdom.'

Pradip Gajjar, a Hindu leader, said: 'This is a Christian ceremony for a Christian King. I don't see a problem with that.'

The King has already dramatically slimmed down the scale of the May 6 ceremony, with the service expected to last just over an hour compared with more than three hours for his mother's crowning.

Only about 2,000 guests and dignitaries are set to be invited – including more than 850 community and charity heroes – compared with the 8,000-plus peers and commoners who witnessed the 1953 ceremony.

The dramatically reduced guest list has led to some grumbles at Westminster, with only about 50 backbench MPs and 50 peers not holding high office able to attend.

However, disappointed MPs and peers can apply for up to 400 'pavement tickets' to watch from outside the Commons as the procession passes to and from Westminster Abbey. The row over the Coronation comes after Royal biographer Robert Jobson revealed that the late Queen thought the Duke and Duchess of Sussex's behaviour was 'quite mad' and that Harry was 'so consumed' by his love for Meghan it was 'clouding his judgment'.

In his book Our King, serialised in the Daily Mail and The Mail on Sunday, he also revealed how the Queen had Sandringham's library swept for bugs in 2020 ahead of the Megxit summit, such was her concern over the privacy of the meeting with Harry. And he told how the Princess of Wales found doing a walkabout with the Sussexes two days after the Queen's death 'almost unbearable', such was the ill feeling between the two couples.

END