The Duke and Duchess of Sussex are expecting a baby in spring 2019, Kensington Palace has announced.
The newly-wed couple arrived in Sydney on Monday ahead of a 16-day tour which will take in Australia, New Zealand, Fiji and Tonga.
In a statement, Kensington Palace said: "Their Royal Highnesses The Duke and Duchess of Sussex are very pleased to announce that The Duchess of Sussex is expecting a baby in the Spring of 2019.
"Their Royal Highnesses have appreciated all of the support they have received from people around the world since their wedding in May and are delighted to be able to share this happy news with the public."
Harry and Meghan were wed at Windsor Castle in May and the news was announced on the eve of their first tour outside the UK and Ireland.
The Queen, the Duke of Edinburgh, the Prince of Wales, the Duchess of Cornwall and Duke and Duchess of Cambridge are said to be "delighted" for the couple.
Doria Ragland, the mother of the duchess, is "very happy about this lovely news" and "looks forward to welcoming her first grandchild".