The Duchess of Sussex, Meghan, has given birth to a boy with husband Prince Harry by her side.
The as yet unnamed baby was born at 5.26am UK time on Monday, weighing 3.2kg.
Both Meghan and the baby, the couple’s first child, were healthy and well, Buckingham Palace said in a statement.
Prince Harry described his son as “absolutely to die for”.
“How any woman does what they do is beyond comprehension but we’re both absolutely thrilled and so grateful to all the lovely support from everybody out there,” a smiling Harry told reporters in Windsor, west of London, where the couple live.
“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.”
Harry, 34, was present for the birth and 37-year-old Meghan’s mother Doria Ragland was also with the couple at their home, Frogmore Cottage, on the estate of Windsor Castle, where they married in May last year.
Queen Elizabeth and other members of the royal family were delighted by the news, the palace said.
British Prime Minister Theresa May sent congratulations.
“Wishing you all the best at this happy time,” she told the royal couple on Twitter.
The baby is 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 and any such title would have to be bestowed by the Queen by issuing what is known as a letter patent.
Albert, Philip, Arthur and James are the favourite names for the child, according to bookmakers.
Unlike Harry’s brother Prince William and his wife Kate, who posed for massed photographers outside a London hospital just hours after their three children were born, Harry and US-born Meghan are expected to take part in only a limited photo call in the grounds of Windsor Castle within a few days of the birth.
For some the child’s birth will represent a significant moment for the monarchy, becoming the first mixed-race baby born into a senior position in British royalty, according to royal experts.
“It’s symbolic of a more modern monarchy. It appeals to people across the world,” royal biographer Claudia Joseph told Reuters.
“They will be able to identify with the royal family as never before.”
Others note however that Meghan, whose mother is African-American and father is white, has been the target of racist commentary on social media.