Britain's Duchess of Cambridge gives birth to a boy Britain's Duchess of Cambridge Kate gave birth to a boy on Monday afternoon. He is now the third in line to the British throne. British Prime Minister Cameron described the birth as "an important moment in the life of our nation." A Town Crier announces the birth of Prince William and his wife Catherine's baby boy in front of St Mary's Hospital in London, on July 22, 2013. Xinhua/Yin Gang LONDON, July 22 (Xinhua) -- Britain's Duchess of Cambridge Kate gave birth to a boy on Monday afternoon. The baby, about 3.8 kilograms in weight, was born at 4:24 p.m., according to sources with the Kensington Palace. This is the first time in 119 years that there have been three generations waiting in succession to the British throne. "Her Royal Highness and her child are both doing well and will remain in hospital overnight," said the palace in a statement. The Queen, The Duke of Edinburgh, The Prince of Wales, The Duchess of Cornwall, Prince Harry and members of both families have been informed. A Buckingham Palace spokesman said the Queen and Duke of Edinburgh are delighted at the news that Kate has given birth to a son. The Prince of Wales said that he was "enormously proud and happy to be a grandfather for the first time," adding that it was "an incredibly special moment for William and Catherine." Speaking outside 10 Downing Street, British Prime Minister David Cameron described the birth as "an important moment in the life of our nation." "It has been a remarkable few years for our royal family - a royal wedding that captured people's hearts, that extraordinary and magnificent jubilee and now this royal birth - all from a family that has given this nation so much incredible service," he said. As the tradition, an official notice of birth is placed outside the Buckingham Palace Outside St Mary's Hospital many royal fans had camped there for two weeks along with photographers from around the world. They waved national flags and sang "Happy Birthday to You" aloud for the new royal baby. Terry Hutt, 78, was from Cambridge and have camped for 12 days. "This is my longest experience to camp," he said. But it is lovely to be around. I am glad to see it is a healthy baby. 31-year-old Teba Diatta made a cake for the occasion, on which she wrote: "Come on Kate, we can't wait. Give us something to celebrate. She told Xinhua that the cake was made just for fun, which she would share with reporters later. "It is not easy for them," she said. Even some tourists joined in the revelry. Miriam, 62, was from Italy. "I am traveling in London while my sister told me 'Kate is in labor'," she said. So I came here immediately. When she suddenly realized that she left her camera in the hotel, Miriam bought a disposable one. "I will make a special album for the royal baby," she beamed. There will be a 41-gun salute at London's Hyde Park and 62 rounds fired at the Tower of London on Tuesday to herald news of the birth. Already more than a week past her due date, Kate was taken through a side entrance of the St. Mary's Hospital at around 6 a.m. Her husband Prince William was with her during the delivery. The Duke of Cambridge was born in the same hospital in 1982, as well as his brother Prince Harry. William and Kate held a spectacular wedding at Westminster Abbey in April 2011. Kate was confirmed as pregnant last December. Obama congratulates new birth in British royal family WASHINGTON, July 22 (Xinhua) -- U.S. President Barack Obama on Monday extended his congratulations to British Prince William and his wife Kate for the birth of their first child. New Zealand PM welcomes new arrival to royal line WELLINGTON, July 23 (Xinhua) -- New Zealand Prime Minister John Key on Tuesday congratulated Prince William and his wife Catherine on the birth of the baby boy, and the country marked the arrival of the third in line to the head of state with a 21-gun salute in the earthquake-shaken capital of Wellington. Catherine's pregnancy brings back memories of Diana For Britons waiting for the birth of the royal baby, many are able to cast their minds back to the days of Diana and the births of her two sons, now Princes William and Harry.