European royals save the date for Prince William's wedding

European royals have received early save-the-date messages inviting them to the wedding of Britain's Prince William and Kate Middleton.

The VIP guests -including William's godfather Greece's former King Constantine and his family and royals from Spain, Holland, Norway, Sweden, Denmark and Belgium - were sent the messages by fax as protocol dictates that sovereigns are given earlier warning than foreign heads of state and non-VIP guests.

Traditional gold-embossed, handwritten invitations will be sent to 1,800 guests by the Lord Chamberlain's Office next month and royal aides revealed faxes were deemed the most "efficient" way of notifying the various royal families.

A St James's Palace aide told the Daily Mail: "The Lord Chamberlain's Office does give a heads-up to royal families first, in line with protocol."

A Buckingham Palace courtier added: "Faxes have been used before for large-scale events. They are an efficient and polite way to inform people as quickly as possible."

King Constantine, his wife Queen Anne-Marie and their eldest son Crown Prince Pavlov will attend with a spokesman saying: "They received a fax in the last few days."

Crown Prince Alexander of Serbia and his wife, Crown Princess Katherine, have also confirmed their attendance with a statement on their website declaring "Their Royal Highnesses are delighted to attend the marriage and are very happy for the young couple."