AN internet buyer from Leeds has bought a slice of the Prince and Princess of Wales's wedding cake for £1,850 at an auction - more than 40 years after Charles and Diana tied the knot.

The large piece of cake icing and marzipan base from one of the 23 official wedding cakes features a sugared onlay of the royal coat-of-arms coloured in gold, red, blue and silver.

It was given to Moya Smith, a member of the Queen Mother's household at Clarence House, who preserved the topping with cling film.

She kept it in an old floral cake tin and taped a handmade label to the lid, reading: "Handle with Care - Prince Charles & Princess Diane's (sic) Wedding Cake", which she signed and dated 29/7/81.

Mrs Smith's family sold the cake in 2008 to a collector, but it has come up for auction again, coinciding with what would have been the Waleses' 40th wedding anniversary on July 29.

The cake went under the hammer at Dominic Winter Auctioneers in Cirencester, Gloucestershire, on Wednesday afternoon, and was expected to fetch between £300 and £500.

But a flurry of bidding from across the world led to an internet buyer in Leeds securing the slice for £1,850.

Speaking after the sale, auctioneer and royal memorabilia specialist Chris Albury, of Dominic Winter Auctioneers, said: "We were amazed at the numbers of people wanting to bid on this large and unique piece of royal cake icing.

"It seemed to get far more attention than when we sold it with a Charles & Diana thank you letter 13 years ago.

"There were lots of inquiries from bidders, mostly in the UK, USA and several countries in the Middle East.

"The bidding started at £300 and with commission bids, the internet and phone bidding, quickly rose to the winning price of £1,850.

"It was bought by an internet bidder in Leeds.

"As yet we haven't had a chance to speak to them to get a reaction or ask why they bought it, but it seems that this was an irresistible piece of royal memorabilia history for many."

Mrs Smith began her career at Clarence House in the kitchen before moving on to more general duties on the recommendation of Lady Jean Rankin.

Prince Charles married Lady Diana Spencer in St Paul's Cathedral on July 29 1981.

In addition to their main official five-tier wedding cake, some 22 other wedding cakes were supplied by various manufacturers.

Mr Albury said he believed the slice up for auction is likely to have come from either the side of a cake, or from the top of a single-tier cake.

The cake was sold on Wednesday along with printed ceremonial and order of service programmes for the wedding, and a memorial Royal Wedding Breakfast programme for Buckingham Palace.

Charles and Diana's marriage was not to last and they split 11 years later in 1992, and divorced in 1996.

She went on to champion the disadvantaged but died suddenly in a Paris car crash in 1997, a year after the divorce, when sons William and Harry were aged just 15 and 12.