In this file photo taken on April 23, 2018 Britain's Prince William, Duke of Cambridge carries his newly-born son, Britain's Prince Louis of Cambridge from the Lindo Wing at St Mary's Hospital in central London. (AFP/Ben Stansall)
Britain's Prince Louis, the baby son of Prince William and his wife Kate, is due to be christened at a private ceremony at St James's Palace in London on Monday.
Archbishop of Canterbury Justin Welby, the spiritual leader of the world's Anglicans, will lead the service at the Chapel Royal with close friends and family in attendance.
Welby, who will baptise the baby by pouring holy water from the River Jordan over his head, said the event would be "very nerve-wracking" but "a great privilege".
Louis is the third child of the Duke and Duchess of Cambridge and is fifth in the line of succession to the British throne after his grandfather Prince Charles, his father William and his siblings Prince George and Princess Charlotte.
He is also one of Queen Elizabeth II's seven great-grandchildren.
The service is due to start at 1500 GMT and last 40 minutes, while the list of godparents is expected later on Monday.
The 16th-century chapel, which is not accessible to the public, is where Louis' four-year-old big brother George was christened in 2013.
Charlotte, who is three, was christened in 2015 at the 16th-century Church of St Mary Magdalene on the queen's country estate in Sandringham in eastern England.
Louis was born on April 24 -- St. George's Day, England's national day -- at St Mary's hospital in central London weighing eight pounds and seven ounces (3.8 kilogrammes).
Royal fanatics, who had been camped outside the hospital wing for several days in anticipation, jumped for joy and popped open champagne as the news of his birth was announced.
Tony Appleton, a town-crier dressed in a flamboyant red uniform, announced the news from the steps of the hospital to a crowd of supporters and media.
The birth was also announced on the display screen atop the 189-metre (620 feet) BT Tower in London, with the message "It's a boy!"