The Duke and Duchess of Cambridge have proudly showed the world their baby son, a future king, before taking him home.

William and Kate began their new lives as parents, cradling their baby prince and posing for pictures on the steps of the Lindo Wing of St Mary's Hospital in London.

The Duchess held her son first and the couple looked relaxed and smiled broadly as the world's media captured the moment.

William later held his son and walked forward with his wife to answer a few questions. He began by joking: "He's got a good pair of lungs on him, that's for sure. He's a big boy, he's quite heavy. We are still working on a name so we will have that as soon as we can."

He added: "It's the first time we have seen him really so we are having a proper chance to catch up." The Duchess, who still had a bump under her summer dress, said: "It's very emotional, it's such a special time. I think any parent will know what this feeling feels like."

Her husband agreed: "It's very special." He added: "I'll remind him of his tardiness when he's a bit older. I know how long you've all been standing here so hopefully the hospital and you guys can all go back to normal now and we can go and look after him."

A crowd of well-wishers who were gathered at the entrance to Kensington Palace cheered as the Duke and Duchess arrived home with their baby. William smiled from behind the wheel and Kate, who was sitting on the back seat, waved with her son next to her in a baby seat.

Speaking outside hospital, William said: "He's got her looks, thankfully," while Kate replied: "No, no, I'm not sure about that." Joking about his apparent lack of hair the Duke said about his son: "He's got way more than me, thank God".

The couple's good humour continued during their brief questioning from the press with Kate revealing that her husband was a hands on dad. Asked about changing nappies William said: "We've done that already," and Kate said "he's done his first nappy already".

The Duke looked at ease holding his son and after speaking to the press for a few minutes returned inside the Lindo Wing with his wife. The couple soon emerged with their son in a baby seat and William carefully fitted it onto the backseat of a Range Rover beside his wife before driving his family home.