Ms Read toiled over the piece for 280 hours, and just hopes the new baby will get a chance to be wrapped up in it.
The life-long knitter and award-winning spinner from Cambridge was stunned to be asked to come up with a present for the Duke and Duchess of Cambridge.
"It was quite a daunting task, but I said 'yes', and then I thought, 'What have I gotten myself in for?'" Mrs Read said today.
Mr Key also extended his congratulations to The Prince of Wales and Duchess of Cornwall, and The Queen and Prince Phillip, on the arrival of the newest member of the Royal Family.
"New Zealanders remember with fondness the visit of Prince William when he was just a toddler, playing on the lawn of Government House with a Buzzy Bee. It would be a great pleasure to welcome Prince William's son to New Zealand as well," he said.
As well as the shawl, and with the blessing of the Duke and Duchess of Cambridge, an invitation was sent to knitters around the country to knit baby singlets to give to new parents at local maternity and neonatal units on the couple's behalf.
"On behalf of the people of New Zealand, I wish Prince William, Catherine and the Royal Family all the very best," Mr Key said.
A 21 gun salute will be fired from Point Jerningham, Wellington today to celebrate the birth of the Prince of Cambridge.