Sweden's Crown Princess Victoria has given birth to her first child, a baby girl who will be groomed to one day become the country's queen.

Victoria's husband, Prince Daniel, said the girl, who is second in line to the Swedish throne, was born at 4.26am (0326 GMT) at the Karolinska University Hospital in Solna, a suburb of Stockholm. She was 20 inches (51 centimetres) long and weighed 7.23 pounds.

"When I left the room the little princess was sleeping on her mother's chest and they were looking very cosy," an emotional Daniel told reporters. "The little daughter and the crown princess are doing very well."

Victoria, 34, is next in line to the throne held by her father, King Carl XVI Gustaf, since 1973. Sweden changed the constitution in 1980, three years after Victoria was born, to allow the eldest heir to inherit the throne, regardless of gender. Before that female heirs were excluded.

Daniel said the king and Victoria's mother, Queen Silvia, had been informed of the birth and "are very happy".

Victoria married Daniel, a commoner and her former personal trainer, in June 2010. In August last year, the Royal Court announced that Victoria was pregnant.

Sweden's top news sites proclaimed the royal birth with bold headlines, as TV stations broadcast live from the hospital. The Royal Court made the announcement on its website and, in a modern touch, on its Facebook page.

As is custom when an heir to the throne is born, the Swedish armed forces were to celebrate the news with two 21-gun salutes at noon in Stockholm and other cities around Sweden.

The country had eagerly awaited the announcement all night after the Royal Court confirmed after midnight that Victoria had checked in to the hospital.

Daniel said he was "pretty nervous" during the birth and that he cut the baby's umbilical cord. The king will announce the girl's name later this week, he said.