Last May, millions across the world tuned in to watch Queen Elizabeth II's grandson Prince Harry tie the knot with his American fiancee, Meghan Markle, with the media feting the couple as the epitome of glamour and royal modernity.

But less than a year later, the couple have found themselves on the receiving end of much less flattering coverage as they prepare for the birth of their first child this spring.

"Frown Jewels: Meg is banned by Queen from using Di gems," the front page headline on Britain's biggest-selling newspaper, the Sun, said on Thursday over a story which claimed the monarch had banned Meghan from wearing royal jewelry, a sign of growing tensions between Harry's wife and senior Windsors.