A former royal butler who is facing a jail sentence for having sex with underage boys once ushered a young victim into conversation with Queen Eliza-beth the Queen Mother at a Clarence House Christmas party.

Paul Kidd, 55, claimed to know the secrets of life below stairs at Buckingham Palace, where he worked for six years, and charged up to £4,000 on the after-dinner circuit for his “hilarious” anecdotes about royal service.

What he did not talk about was that he also seduced and abused boys. Yesterday, just before his trial on paedophile charges was due to start in Manchester, he changed his plea to admit-offences covering four decades.

Kidd, of Stalybridge, Cheshire, was appointed butler to the Queen in 1976 and worked at the Palace for six years before transferring to Clarence House to carry out similar work for the Queen Mother. He claimed to have looked after three US presidents and every monarch in Europe during that time, and later boasted that in 1979 he was awarded the Most Noble Order of Merit by the West German President.

His secret life was exposed last year after a newspaper carried an interview with him as part of its coverage of the tenth anniversary of the death of Diana, Princess of Wales. A victim, now in his forties, complained to police that Kidd had abused him in the early 1980s, when he was 13 to 16.

When police raided Kidd’s flat they discovered indecent videotapes in his locked safe, and encrypted files containing similar material on his computer.

Altogether he had more than 18,000 images of young boys of various levels of indecency. It was suggested to the investigating team that the password for his encrypted files – “pickles” – was the name of a royal corgi.

Examination of the videos led police to a second victim, now 18, who said he had been abused not only by Kidd but also by a second man, David Hobday, 56, when he was 14. A third victim told police that he had been abused in the late 1970s. He said that, as a teen-ager, he had been taken to the Queen Mother’s Christmas party and introduced to her as a friend over tea.

Kidd’s use of a webcam, the number of indecent images, and the sharing of at least one victim between two men has prompted suggestions that he could have been part of a larger paedophile ring.

Kidd, who has worked in children’s homes and met one of his victims while working as a nurse, was said by the prosecution team to have an easy charm. One source described him as a “brilliant” sexual groomer. He had said that he was bisexual but that he had changed his ways after becoming a practising Christian. After his arrest he said would leave his fate with God. Kidd, who stood alongside Hobday in the dock at Minshull Street Crown Court, Manchester, admitted offences dating from 1975 to 2006.

He pleaded guilty to making indecent images of children, possessing indecent images of children, indecent assault, sexual activity with a child, sexual touching of a child and causing or inciting a child to engage in sexual activity. Hobday, of Dukinfield, Tame-side, pleaded guilty to sexual activity with a child and possessing an indecent video of a child.

Judge Khokar told the men that they were likely to be jailed. He ordered that they be held in custody while presentence reports were drawn up.

Kidd, who has a son who lives in America, stood as a UKIP candidate in Dukinfield and Stalybridge in last year’s local government elections. He has been suspended from the party.

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