The Royal Separation: Joint coronation 'would make farce of ceremony': The separation finds some echoes from history. Steve Boggan and David Keys report

WHEN the Prime Minister announced yesterday that the Princess of Wales could one day become Queen, historians are likely to have pondered the events of 19 July 1821, the day George IV was crowned King.

That was the last time an estranged wife tried to claim her crown at a coronation, and it ended farcically with the pathetic figure of Princess Caroline banging her fists on the locked doors of Westminster Abbey.

John Major's assertion that there was nothing to prevent the Princess of Wales from becoming Queen was correct; there is no statutory impediment. As the future Supreme Governor of the Church of England, the Prince of Wales must be seen to obey canon law which still does not recognise divorce.

Therefore, if the couple do not divorce, they remain married in the eyes of the Church. If he becomes King, she becomes Queen. The Church appeared to change its attitude somewhat yesterday, when the Archbishop of York, Dr John Habgood, issued a statement on behalf of himself and the Archbishop of Canterbury, Dr George Carey, saying marital status would not affect the Prince's position; he can divorce if he wishes. But not all historians and constitutional experts agreed.

The Rev Edward Norman of Christ Church College in Canterbury, Kent, an author of several books on church and state, said: 'If there were a divorce, the King, who is the Supreme Governor of the Church of England, or heir who broke the canon law of the Church of England would feel obliged to abdicate.'

Buckingham Palace said yesterday that there would be no question of divorce or of the Princess of Wales being left out in the cold should Charles be crowned King. During little more than three weeks of horse-trading over the terms of the separation, it is understood it has been agreed that the Princess of Wales will be at the Prince's side at any coronation.

However, some observers raised questions about the possibility of such an arrangement in the long term. If there is anything less than harmony between the estranged couple, marching into Westminster Abbey together may be difficult.

'The sovereign is the Supreme Governor of the Church of England and the coronation is a religious ceremony,' said Vernon Bogdanor, reader in government at Oxford University. 'Would it be appropriate in those circumstances to take those vows when you are formally separated?

'That is not a matter of statute, it is a matter of convention and feeling. One cannot give a precise answer to that question; there is no other precedent.'

On the question of divorce, Mr Bogdanor said: 'There is no statute that says the King cannot get divorced. However, again the King is Supreme Governor of the Church of England; could you contemplate a divorced Archbishop of Canterbury? I think you would have to say you couldn't - so can you have a divorced King? It is a difficult question.'

The prospect of a joint coronation of an estranged royal couple 'would make a farce of the coronation service, which is the most sacred and historic symbol of English monarchy', said Dr Pauline Croft, an authority on 17th-century England at Royal Holloway University of London. 'The coronation has always been so precious in English history. I would find a coronation service in which both were crowned disquieting, given that all the world knows they are living separate lives. Such an event would inevitably bring the monarchy into disrepute.'

Although there was much public disquiet over the announcement, the couple's problems are nothing new in the monarchy. In the 12th century, King Henry II had his wife placed under house arrest for plotting against the crown, and in the 14th century Edward II was on such poor terms with his wife that she actually deposed him.

Henry VIII had a succession of marital problems and solved them by divorce and execution. James I and his wife, Anne of Denmark, became estranged after family rows and the King's penchant for taking male lovers. And Charles II openly cavorted with mistresses in front of his wife, Catherine of Braganza (Portugal). But the court was so debauched that the royal couple's situation was acknowledged as the social norm.