Those attending the April 8 civil ceremony in Windsor Guildhall will include the children that the heir to the throne and Parker Bowles had from their previous marriages, the source told AFP late Monday.

"There will be 30 people present for that (civil ceremony)," in keeping with the couple's desire for a "low-key" affair, the source said on condition of anonymity.

The source denied a report in The Times newspaper that 200 would attend the civil ceremony.

No details have yet emerged for the guest list for the civil wedding, though Queen Elizabeth II and her husband Prince Philip have decided not to attend the civil ceremony to keep the event a low-key affair, the family has announced.

Royal experts said the queen, as head of the Church of England, believed that a civil wedding in an ordinary town hall diminished the monarchy as an institution.

However, the queen will be present for the service of prayer and dedication afterward at Saint George's chapel in Windsor Castle, which the source close to the royal family said will have 700 people attending.