Crowds of well-wishers gathered outside a London hospital Tuesday, hoping to catch the first glimpse of the newest heir to the British throne.
Prince William and his wife Kate are expected to soon leave the facility, giving the public its first look at the royal baby, whose name has not yet been announced.
Impromptu celebrations were held Monday following the news of the birth. Kensington Palace says both Kate and her mother are "doing well." Prince William said in a brief statement, "we could not be happier."
The celebrations will continue Tuesday, with ceremonial royal artillery gun salutes expected to sound across London in honor of the birth.
After the baby's birth, Prime Minister David Cameron called it an "important moment" for Britain. He said a "proud nation is celebrating."
"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 have given this nation so much incredible service, and they can know that a proud nation is celebrating with a very proud and happy couple tonight."
At Buckingham Palace, crowds cheered and rushed toward the gates as the news of the royal birth was announced. Many people stayed outside the palace late into the night.
The new baby will displace Prince Harry as third in line to the British throne, after Queen Elizabeth's eldest, Prince Charles, and his son, Prince William.
Soon after the royal birth, messages of congratulations began pouring in from around the world.
In a statement from the White House, U.S. President Barack Obama and first lady Michelle said they wished the couple "all the happiness and blessings parenthood brings."
Under a new law in Britain, still to be enacted by the country's parliament, the child would have been heir to the throne even if it were a girl. For centuries, preference was given to male heirs.