Third baby on the way for Duke and Duchess of Cambridge

The Duke and Duchess of Cambridge are expecting their third child

The Queen is "delighted" with the news, Kensington Palace said in a statement.

The announcement was made as the the Duchess is suffering from severe morning sickness, as she did with her previous pregnancies, forcing her to cancel a public engagement she had later today.

The statement said: "Their royal highnesses the Duke and Duchess of Cambridge are very pleased to announce that the Duchess of Cambridge is expecting their third child.

"The Queen and members of both families are delighted with the news.

"As with her previous two pregnancies, the Duchess is suffering from hyperemesis gravidarum.

The latest addition to the Cambridge family will be a great-grandchild of the Queen and the Duke of Edinburgh.

He or she will be fifth in line to the throne, pushing uncle Prince Harry into sixth place.

Irish bookmaker Paddy Power made Alice and Arthur their early favourites.