The Duke and Duchess of Cambridge have introduced their baby boy to the world, standing proudly on the steps of the Lindo Wing with their son.

The royal infant, wrapped up against the cool spring weather, nestled in the arms of his mother as the couple posed for pictures.

Kate looked in good health after giving birth this morning to her as yet un-named prince, who is fifth in line to the throne.

The couple then re-emerged from the hospital with the prince in a baby seat.

William placed him in the rear of the car with Kate and then drove them away under police escort to Kensington Palace.

As he left, the duke told reporters he was "very happy, very delighted, thank you".

He added: "Thrice the worry now."

And to reporters, he said: "We didn't keep you waiting too long this time."

The tiny fingers of their son could be seen moving as the couple looked around smiling at the crowds.

The duchess wore a red Jenny Packham dress with a contrasting white collar.

They went inside for a few minutes to put their son in a baby carrier and emerged hand in hand.