Catherine, Duchess Of Cambridge has pulled out of an official trip to Malta as she continues to battle severe morning sickness.

The pregnant royal had been due to embark on her first solo overseas visit later this week (beg15Sep14), but she has now withdrawn from the engagement due to her condition, known as hyperemesis gravidarum.

Her husband, Prince William, will take the trip in her place.

A statement from royal office Clarence House, posted on Twitter.com, reads, "The Duchess of Cambridge will no longer visit Malta this weekend. The Duke of Cambridge will undertake the visit instead #RoyalVisitMalta... HRH (her royal highness) continues to suffer from hyperemesis gravidarum. The decision was taken on the advice of doctors... The Duke of Cambridge is honoured to represent The Queen on the visit, which commemorates the 50th anniversary of Malta's Independence (sic)."

The news comes after the Duchess pulled out of plans to attend her brother-in-law Prince Harry's 30th birthday party this week (beg15Sep14).

Catherine, Duchess of Cambridge and Prince William are already parents to a son, Prince George, who was born last year (13).