Princess Charlene and Prince Albert. [Photo/Agencies]

Monaco's Princess Charlene has given birth to twins.

The 36-year-old royal and her husband Prince Albert welcomed a baby boy and a girl into the world on Dec 10 after she was admitted to the Princesse Grace hospital in the principality, where she is thought to have given birth via caesarian section.

Local newspaper Monaco Matin first reported the news but it is not known whether 56-year-old Albert was by the South African-born beauty's side or not during the birth.

The little boy will automatically be the heir to the throne regardless of whether he was the first born of the two or not.

The births have not been officially announced by the Palais Princier yet but when they are then they will be recognized by 42 cannon shots - double that of a single royal baby's birth.

Charlene announced she was pregnant in May and the former Olympic swimmer recently confirmed she was expecting twins and feeling fantastic about her pregnancy.

She said: "I feel absolutely great."

In October, New York plastic surgeon Dr. Jon Turk revealed Albert had been working hard to childproof the royal couple's home ahead of their impending new arrivals, and he was particularly concerned about the sharp edges on the tables.

He explained: "The princess told me that he's been walking around their residence and their summer house, starting to childproof the houses.

"He's worried about the corners of tables. And she's saying they're not even born yet! He's also going to put air in all the balls for soccer and basketball. He's already getting ready and it's still years away before they can play with a ball."

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