The Duke and Duchess of Cambridge are expecting a third child.

Kate and William made the announcement via Twitter this evening.

As with her previous pregnancies, the Duchess is suffering from Hyperemesis Gravidarum, a severe form of morning sickness.

Kensington Palace has advised she will not carry out royal duties while dealing with the illness.

There’s no word yet on the due date for Prince George and Princess Charlotte’s new sibling, but bets are being taken on the name.

UK correspondent Malcolm Stuart told Ross and John that ‘Alice’ is the favoured name for a girl, and ‘Arthur’ the favourite for a boy, with ‘Alexander’ and ‘Alexandra’ also hotly-tipped.

‘Diana’ is at 20-1 with bookmakers. Other popular options are ‘Victoria’, ‘Elizabeth’, ‘James’, ‘Philip’, and ‘Henry’.

Click PLAY to hear more from Malcolm in the UK

Read the press release in full ↓ pic.twitter.com/vDTgGD2aGF

— Kensington Palace (@KensingtonRoyal) September 4, 2017