LONDON — Buckingham Palace said Tuesday that the Queen would not attend the civil marriage ceremony of her son Prince Charles and Camilla Parker Bowles.

The Queen would, however, attend the church blessing of the marriage at St. George's Chapel in Windsor Castle following the civil ceremony, the palace said.

The Press Association news agency reported that Prince Charles' sons, Prince William and Prince Harry, and Parker Bowles's children, Tom and Laura, were expected to be present for the April 8 civil wedding in the Guildhall at Windsor.

"The Queen will not be attending the civil ceremony because she is aware that the prince and Mrs. Parker Bowles wanted to keep the occasion low key,'' a palace spokeswoman said on condition of anonymity.

"Clearly if the Queen were to attend, the occasion would no longer be, by definition, low key,'' she said.

The spokeswoman insisted the Queen's decision was "not a snub,'' saying the monarch was "very pleased to be giving the wedding reception at the castle'' after the ceremony.

Charles and Parker Bowles are marrying in a civil ceremony because the Church of England, of which Charles will become supreme governor when he takes the throne, traditionally frowns on church marriages for divorcees whose spouses are still alive.

Charles, 56, divorced Diana in 1996. She died in a car accident the next year. Parker Bowles, 57, also is divorced, and her ex-husband is still alive.

The wedding was originally slated to be held at Windsor Castle, but the couple announced last week the ceremony would be held at the Windsor town hall.

The change was a practical one: under British law, registering the castle as a wedding venue would mean opening it up to commoners' weddings. The prince's Clarence House office said holding the service in the 17th-century town hall also would allow the public to see the newlyweds arrive and leave, and would include the town in the day's events.

A blessing led by Archbishop of Canterbury Rowan Williams after the ceremony will still take place at the castle's St. George's Chapel, followed by a reception at the castle's state apartments.

The royal household also said Tuesday that Charles will not have a best man for the ceremony. Heirs to the throne are usually accompanied by two "supporters'' -- the royal term for best man -- when they wed, and it had been speculated that Charles's sons William and Harry would perform the role.

"There will be no best man or royal supporters. It's not that sort of wedding,'' said a spokesman for the prince, speaking with customary anonymity.

"The two boys will have a role throughout the wedding in so much as being by their father's side.''