Kate Middleton
The Duke and Duchess of Cambridge welcomed Prince George in July 2013.

After days of speculation, Kensington Palace has confirmed that the Duchess of Cambridge will not be travelling to Malta this weekend for her planned royal visit.

The Duchess of Cambridge, who is pregnant for the second time, is battling Hyperemesis Gravidarum, the same illness she was hospitalised with in the early months of her first pregnancy with Prince George in 2012.

She had been scheduled to travel to the Mediterranean Island to attend the official commemoration of Malta's independence on Saturday on the Queen's behalf.

During the solo visit, she planned to visit the national library to see letters from past British monarchs Henry VIII and George II and a complete a number of tours.

But on the advice of doctors, the couple have decided that she should remain at home, where she can continue to rest.

Prince William will take part in the Independence Day celebrations in his wife's place.

"The duke is honoured to represent Her Majesty the Queen on the visit, which commemorates the 50th anniversary of Malta's independence," a palace spokesperson said in a statement.

"The visit itinerary remains unchanged."

This is the third royal engagement the mother-of-one has been forced to bow out of in recent weeks.

After Clarence House announced that the royal couple were expecting their second child, she pulled out of the opening of Oxford University's new Chinese studies centre, and was also unable to attend the opening ceremony and start of the Prince Harry's Invictus Games.