William and Kate show their prince to the world

Prince William and Kate Middleton today gave the world the first glimpse of the baby destined to be Britain's King one day as they posed with their newborn son while leaving the St Mary’s Hospital.

The royal couple emerged on the steps of the hospital in London in the evening with their newborn baby boy for the first time.

The Duke and Duchess of Cambridge gave the world a glimpse of the Prince of Cambridge for the customary royal family portrait amid cheers from the crowd of well-wishers and mediapersons from across the globe who were camped outside the hospital.

The baby raised a tiny hand above his white blankets but remained quiet.

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"He has a good pair of lungs on him and he's quite heavy. We are still working on a name," said William, taking the little prince from his wife's arms.

He said: "It's the first time we have seen him really so we are having a proper chance to catch up."

"He's got her (Kate) looks, thankfully," he added, when asked who the baby looks like.

Speaking to the waiting crowd, Prince William said: "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."

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Thirty one-year-old Kate said: "It is a very emotional moment, like any new parent would know".

William, 31, dressed casually in a blue shirt with rolled up sleeves, and Kate wearing a light blue polka dotted dress, then took their 26-hour-old baby boy wrapped in a white blanket back into the hospital to secure him into a car seat before stepping out again into a Range Rover to be driven away to their home in Kensington Palace where Kate's sister Pippa was reportedly waiting.

In the minutes leading up to their exit at 19:13 (local time), Kensington Palace had issued a statement confirming that the Duchess was to be discharged in the evening.

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Just before they made their exit, Prince Charles had visited the the Lindo Wing of the hospital to see his first grandchild and the third in line to Britain's throne.

Accompanied by wife Camilla Parker-Bowles, Charles saw the newest royal heir for the first time at the same wing where both his own sons William and Harry were born.

He had triggered a frenzy among the waiting reporters and camerapersons as he said on his departure: "He (royal baby) is marvellous. You will see in a minute".

It was the first indication that the royal couple were likely to depart the hospital with the newborn later on in the evening.

His mother, Queen Elizabeth II, had sent a message saying she was "absolutely thrilled".

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Earlier in the day, parents of Kate Middleton Carole and Michael Middleton, visited the new mother and their first grandchild at the hospital.

Britain has been in full celebratory mood after Prince William's wife Kate Middleton gave birth to the bouncing baby boy with hundreds thronging the street leading to the hospital.

"We could not be happier," said William, the 31-year-old Duke of Cambridge, in reference to the new prince of Cambridge, whose name is yet to be announced.

The Duchess of Cambridge, 31, on Monday gave birth to the baby boy, weighing 3.8 kilos (8 lbs 6 oz), at the private Lindo wing at St Mary's Hospital in Paddington.

Earlier, William and Kate thanked hospital staff for caring the baby, who was "doing well".

"Mother, son and father are all doing well this morning," a spokesman of the KensingtonPalace, William and Kate's official residence, said in a statement.

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"We would like to thank the staff at the Lindo Wing and the whole hospital for the tremendous care the three of us have received," the Royal couple said in the statement.

"We know it has been a very busy period for the hospital and we would like to thank everyone -- staff, patients and visitors -- for their understanding during this time."

People continued to celebrate the birth of the boy even as congratulatory messages poured in from across the globe.

The fountain in Trafalgar Square was lit up with blue lighting to mark the birth of the third in line to Britain's throne and "It's a boy" was instantly being flashed on the BT Tower in central London.

Queen Elizabeth II was the first to be informed about her newest great-grandson by phone. 

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