The Royal Family is known for maintaining strict code of conduct when it comes to official engagements, especially the dress codes.

Camilla, who is set to fly off to Down Under with husband King Charles for their first international trip since the ascension, made a key decision about what she will be wearing during the trip.

It is understood that the royals are not supposed to wear similar colours to what the senior members are wearing in an effort to not upstage them.

Kate Middleton is fond of the colour blue while Camilla also finds that the colour looks favourable on her. However, bound by the dress codes, Camilla would not wear it often. Now that she is a senior royal member, she gets first pick of the colour.

“The Queen is now able to choose her outfits before all the other women in the Royal Family,” a source told Express.co.uk. “It's part of the royal pecking order and that includes the clothes and colour.

Camilla, who is dressed by Jacqui Meakin, is tipped to wear a lot of blue during the Australia and Samoa trip later this week.

“There was a time when Jacqui [Meakin] was a bit apprehensive to allow blue to be worn at the same time as the Queen [Elizabeth], but she's relaxed that now as long as the blues are very different shades,” the insider explained.

It appears that Camilla is making most of the new-found liberty as she has reportedly racked up a line of blue outfits.