Coronation oath will not be modernised amid reports Charles at odds with church leaders

The religious aspect of the coronation oath that King Charles will take next month will not be changed following reports that the monarch was considering "tweaks" to make it more inclusive.

Charles was said to have been "at loggerheads with church leaders" over the role other faiths should have in the coronation, which is fundamentally a religious – in this case Anglican – service, the Mail On Sunday reported. The Archbishop of Canterbury has denied reports of “tension” between church leaders and Charles.

Catherine Pepinster, an author and religious affairs commentator, further claimed – also in the Mail On Sunday – that this conflict had led to a delay in the order of service being published, something that Buckingham Palace denied.

And last month, The Sunday Times reported that "tweaks" to the oath were being "considered" because Charles was "understood to be keen not to make members of other faiths feel excluded during the coronation".

That report said: "It is thought tweaks to the coronation oath, in which the monarch promises to do his 'utmost [to] maintain in the United Kingdom the Protestant reformed religion' are being considered, in consultation with [Archbishop of Canterbury Justin] Welby."

However, the Cabinet Office has told Yahoo News UK that no changes to the religious element of the coronation oath are planned.

There is still a chance, however, that even if the oath remains the same, additional wording could be inserted before it, which – according to the Constitution Unit at UCL – would allow extra context to be provided without a need for legislative change.

Earlier on Wednesday, the Cabinet Office released a written statement that detailed no legislative action would be required to the modifications planned for the oath Charles will make on 6 May.

This is because the only changes will be to the way realms and territories are referred to, as there are now 14 – when the last coronation took place there were only six.

Making a change like this to reflect the constitutional position regarding territories doesn't require new legislation, but more fundamental changes like removing or significantly enlarging the religious aspect of the oath would have to be put to parliament.

In 1910, an act was passed to change the oath to remove a part that was offensive to Roman Catholics and referred to their teachings as "superstitious and idolatrous".

However, since 1688, each new monarch has publicly committed themselves to Protestantism and promised to "maintain and preserve" the Church of England at their coronations.

It has long been debated how Charles will approach his role as supreme governor of the Church of England, since he made controversial comments in the 1990s about wanting to be "defender of faith", rather than the traditional "defender of the faith" he would one day inherit.

However, Charles walked back these comments in 2018 and after the death of his mother last year said to faith leaders: "I am a committed Anglican Christian, and at my coronation I will take an oath relating to the settlement of the Church of England."

In his first address to the nation as King, Charles also noted that "the role and the duties of monarchy also remain, as does the sovereign's particular relationship and responsibility towards the Church of England – the church in which my own faith is so deeply rooted."

That there will be no legislative action on this occasion and that the Cabinet Office has said there will be no change to the religious aspect of the coronation oath shows that at least for now, the monarchy will continue to rely upon the centuries old tradition and authority of the Church of England to prop itself up.

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