Harry, 34, younger son of heir-to-the-throne Prince Charles, married the U.S. television star Meghan in May at a ceremony that mixed traditional British pomp with a gospel choir and other nods to her American heritage.
British media said Meghan, 37, was believed to be about 12 weeks pregnant. The baby will be seventh-in-line to the British throne.
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“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,” the couple’s Kensington Palace office said in a statement.
The news emerged shortly after the royal couple landed in Australia for their first overseas tour, a busy trip which will also take in New Zealand and the South Pacific islands of Tonga and Fiji.
British media said Harry and Meghan broke the news of their pregnancy to the royal family on Friday, when they attended the wedding of Harry’s cousin Princess Eugenie at Windsor Castle, where Harry and Meghan themselves were married five months ago.
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There had been media speculation for a number of weeks that Meghan might be pregnant, and the couple had made no secret of their desire to have children.
“Hopefully we’ll start a family in the near future,” Harry had said in a TV interview when they announced their engagement in November last year.
The child will not be a prince or a princess unless the queen authorizes such a title before the birth. Instead, royal experts said if a boy, the child would officially be styled the Earl of Dumbarton – one of Harry’s subsidiary titles – and Lady Windsor if a girl.
“My warmest congratulations to the Duke and Duchess of Sussex on the happy news they are expecting a baby in the Spring,” British Prime Minister Theresa May said on Twitter. “Wishing them all the best.”
After their arrival in Australia on Monday, Meghan and Harry were escorted by a motorcade to the residence of Australia’s Governor-General on Sydney’s north shore.
Braving rain, well-wishers lined the streets to Admiralty House where the pair were later spotted by local press enjoying a walk, hand in hand, through the grounds as they recovered from the long plane journey.
Their official duties will begin on Tuesday with a ferry trip across Sydney Harbour and past the Opera House, a visit to Taronga Zoo to see koalas and a viewing of a contemporary indigenous dance troupe.