It's enough to make a royal flush...

Prince William and his oh-so demure fiancée Catherine ­Middleton almost ­faced the ­indignity of being 'WC' on their ­official wedding souvenirs.

But luckily, designers spotted the ­potential for toilet humour. They ­decided 'wee are not amused' and flipped the letters - ­making Kate, 29, the first royal bride to have her initial above the groom's on the official ­commemorative china.

A Palace insider said: "When the ­collection was being designed they ­immediately noticed the problem.

"If they followed tradition with the man's name first, as in the case of Charles and Diana, it would be an embarrassing royal flush."

The final design - personally approved by the royal couple ahead of their April 29 wedding - features a silver C above and intertwined with a gold W.

The letters, on a duck-egg blue ­background, are surrounded by the words: "To celebrate the Marriage of Prince William of Wales and Catherine Middleton."

The English fine bone china items - a plate, a tankard and a pillbox - are also decorated with hearts and doves ­carrying gold rings.

They are embellished with burnished gold and platinum before a final layer of 22-carat gold gilding is applied.

Each set, commissioned by the Royal Collection, was made by hand in Stoke-on-Trent in a process dating back 250 years. The tankard costs £35, the 20cm (8in) plate £40 and the pill box £25, with the profits going to the Royal ­Collection Trust.

A spokesman for Prince William, 28, said: "The Royal Collection has been working on the design since around the time of the engagement - it's a very fast moving process."

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