London: Britain's Prince William and his wife Kate are expecting a third child, their office said on Monday.

"The Duke and Duchess of Cambridge are very pleased to announce that The Duchess of Cambridge is expecting their third child," according to Kensington Palace in a statement.

The announcement comes as a surprise, as there had been little indication that William's wife, the former Kate Middleton, was pregnant.

"The queen and members of both families are delighted with the news," the palace said in a statement.

In a statement, the palace said that 35-year-old Kate was suffering from hyperemesis gravidarum, a severe form of morning sickness which also marked her previous pregnancies, and would not attend a planned event later on Monday.

Kate is being cared for at Kensington Palace.

William and Kate already have two children, Prince George, 4, and Princess Charlotte, 2.

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Prince William and Kate Middleton at Witton Country Park in Darwen, England, last week. Britain’s government says if their first child is a girl she would eventually become queen. Image Credit: AP
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