Is the Princess of Wales about to become a Roman Catholic?: Rumours of possible conversion have been growing, despite the revelation that a dinner party joke took on a life of its own

IT BEGAN as a simple ploy to liven up a dinner party at a country house in Suffolk, but the belief that the Princess of Wales was turning to Roman Catholicism gained ground at a frightening pace.

Reports have been rife of the Princess holding frequent meetings with influential churchmen, of her surrounding herself with new Roman Catholic friends, and of the profound impact on her of meetings with Mother Teresa of Calcutta and the Pope. They seem to provide much of the impetus for her work with Aids victims. But do they mean a conversion is imminent?

Buckingham Palace hoped that the speculation would peter out in March when Anthony Gilbey, a cousin of James Gilbey, the heir to the gin fortune and the man who allegedly professed his love for Diana in the 'Squidgygate' tape, announced that he had started the rumours innocently to stimulate conversation at a dinner party.

'I made the story up last summer,' he told the Spectator. 'I told a number of people as if it were based on solemn fact to test their reactions.' In fact, he told his guests that James Gilbey had introduced Diana to his great uncle, Monsignor Alfred Gilbey, a Roman Catholic canon with a reputation for collecting the 'scalps' of converts.

Monsignor Gilbey denied the reports. 'This is an entirely irresponsible and unfounded rumour,' he said last night. 'She has never been to me for instruction.'

But the rumours will not go away. Yesterday, the Daily Mail carried a two-page report of an interview with Fr Antony Sutch, a high-profile Benedictine monk and a housemaster at Downside Abbey public school near Bath. He said he had met the Princess four times, and that she was 'a woman who is looking seriously at Catholicism'.

Conversion was discussed, the implications for Princes William and Harry and the relative ease with which her marriage to the Prince of Wales could be annulled. But within two days of the interview, Fr Antony called the paper to retract his statements and to say he had met the Princess only once. 'I was talking about Catholicism. I was getting excited. I exaggerated or lied,' he said.

It is understood the feeling among Mail executives is that Fr Antony was 'leaned on' to retract what was otherwise felt to have been a sincere account of a burgeoning relationship. Buckingham Palace described the suggestion that the Princess was considering conversion as 'nonsense', and Cardinal Basil Hume, leader of Roman Catholics in England and Wales, 'knew nothing of it', according to his staff.

But a senior Roman Catholic clergyman said there was a genuine curiosity. 'She is quite clearly interested in the Church but she seems to be at the stage where she is talking to people, finding a priest she feels comfortable with and asking questions,' he said. 'Often it takes people years from starting to examine Catholicism to actually converting. The Princess is not under instruction and there are no signs that she is intending to convert yet.'

If she were to convert, academics are divided over the constitutional implications. Vernon Bogdanor, a constitutional expert at Oxford University, said the 1701 Act of Settlement is quite explicit. 'It says that no one who is married to a Roman Catholic may ascend to the throne,' he said. 'That would debar the Princess from becoming Queen consort and would mean Prince Charles would have to divorce her if he were to become King.' The position of the princes would not change unless they, too, converted; under modern Roman Catholic rules, there would be no pressure on the Princess to encourage their conversion.

However, Lord St John of Fawsley, an expert on the monarchy - and a Catholic - interpreted the Act of Settlement differently. 'It would be fine because the Princess was an Anglican at the time of the marriage,' he said. 'Even if it were not, I am sure the constitution would be changed. It is ludicrous that the King can be married to a Sikh or Buddhist or Hindu, but not a Catholic.'

The feeling among most experts is that a conversion is not on the cards. At Downside yesterday, one monk said Fr Antony had, indeed, met the Princess only once and was definitely not giving her instruction.

'He thought he was being interviewed about an article he wrote in the Spectator about discrimination against Catholics but he got sidetracked,' the monk said. 'Like most of us, Fr Antony is not used to dealing with the press and he got a little carried away. Perhaps he was a little naive.'