The Duchess of Cambridge will not travel to Malta this weekend for her first official solo overseas visit because she is still suffering the effects of acute morning sickness.

Kate, who is pregnant with her second child, had been in doubt after suffering from Hyperemesis Gravidarum - just like her in first pregnancy.

Her husband the Duke of Cambridge will take her place.

In a statement Kensington Palace said: "The Duchess of Cambridge will no longer visit Malta this weekend. The Duke of Cambridge will undertake the visit instead.

"Her Royal Highness continues to suffer from the effects of Hyperemesis Gravidarum. The decision not to travel was taken by the Duke and Duchess on the advice of the Duchess's doctors.

"The Duke is honoured to represent Her Majesty The Queen on the visit, which commemorates the 50th anniversary of Malta's independence.

"The visit itinerary remains unchanged."

The Cambridges made their decision last night in consultation with Kate's doctors.

The visit over the coming weekend had been eagerly anticipated by the people of Malta and would have seen the Duchess celebrate the 50th anniversary of independence.

Highlights of the trip were a visit to the national library to see letters from past British monarchs Henry VIII and George II, Independence Day celebrations and a number of walkabouts.

The Duchess has been suffering another bout of the illness she experienced during the early stages of her first pregnancy.

The illness, which affects 3.5 out of each 1,000 pregnancies, causes severe vomiting and can lead to dehydration, weight loss and a build-up of toxins in the blood or urine, called ketosis.

Her pregnancy has not passed the 12-week stage and there is speculation that the couple's second child could be due in April.