Meghan Markle, the Duchess of Sussex, gives birth to a baby boy

The Duke and Duchess of Sussex have welcomed a baby boy after Meghan Markle went into labour early on Monday morning (local time).

The official Sussex Royal Instagram account said their first-born son weighed 7lbs 3oz or 3.2 kilograms.

The baby, seventh-in-line to the British throne, "is absolutely to die for”, Prince Harry told reporters.

Prince Harry, Duke of Sussex and Meghan, Duchess of Sussex have welcomed a baby boy. Source: Getty Images

"It was amazing, absolutely incredible. As I say, I am so incredibly proud of my wife and, as every father and parent would ever say your baby is absolutely amazing, this little baby is absolutely to die for," a smiling Prince Harry said.

He said they had not yet decided on a name for the child and would make their first appearance as a family in a couple of days' time.

A statement from the royal family said Meghan’s mother Doria Ragland was overjoyed and with the couple at Frogmore Cottage.

The statement said Meghan and the baby are both doing well.

It said that The Queen, The Duke of Edinburgh, The Prince of Wales, The Duchess of Cornwall and other members of the royal family were informed of the birth and were all “delighted with the news”.

A post on the couple’s Instagram account thanked the public for their shared excitement and support during the special time.

Prince Harry speaks to the media after Meghan, Duchess of Sussex, gave birth to a baby boy at Windsor Castle in Berkshire. Source: Reuters

Queen Elizabeth's grandson Harry, 34, and Meghan, 37, a US-born former actress, married in a lavish ceremony at the monarch's Windsor Castle home in May last year.

The baby will be the eighth great grandchild of the 93-year-old queen, the world's longest-reigning monarch, and could be entitled to hold joint British and American citizenship according to nationality rules.

However, the child will not automatically be a prince or a princess as any such title will have to be bestowed by the queen by issuing what is known as a letter patent.

Meghan Markle’s pregnancy was announced in October hours after she and Prince Harry landed in Sydney as part of their royal tour.

Following a day of activities in Sydney, Prince Harry then gushed about her pregnancy for the first time.

“It is great to be back in Australia, and especially even more so this is my wife’s first visit here, so I am very excited to show her this incredible country,” Prince Harry said in a speech at Admiralty House.

“We also genuinely couldn’t think of a better place to announce the upcoming baby, be it a boy or a girl.”

Meghan was not following any of the royal scripts when it came to childbirth preparations.

Prince Harry said he was proud of his wife Meghan Markle following the birth of their first baby. Source: Getty

Unlike Prince Harry’s brother Prince William and his wife Kate, Prince Harry and Meghan chose to keep the details about their baby planning private, despite — or perhaps because of — intense media interest in the baby’s arrival.

The couple had not revealed where Meghan intended to give birth, so there isn’t likely to be a 24/7 media stakeout outside the hospital as was the case for the births of Prince William and Kate’s three children, Prince George, Princess Charlotte and Prince Louis.

Don’t expect a photo of the happy family walking out of the hospital looking picture perfect hours after the birth either — Prince Harry and Meghan have said they want to celebrate privately with their extended family before telling the world a baby has been born.

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