"Welcome to our village wee one," Ardern wrote on Instagram at 6.15pm on Thursday.
CNN, BBC and the Guardian have alerted their millions of readers worldwide of the arrival of Prime Minister Jacinda Ardern and partner Clarke Gayford's new baby girl.
Breaking news banners have popped up across multiple international news outlets following the birth of Ardern's baby at 4.45pm on Thursday.
"Welcome toour village wee one," Ardern wrote on Instagram at 6.15pm on Thursday.
The little girl - whose name has yet to be announced - was born at 4.45pm.
"Thank you so much for your best wishes and your kindness. We're all doing really well thanks to the wonderful team at Auckland City Hospital."
BBC zeroed in on the fact Ardern was the second elected world leader in modern history to give birth while in office, CNN also took a similar approach.
JUST IN: New Zealand Prime Minister Jacinda Ardern becomes the first world leader in nearly 30 years to have a child while in office. She gave birth to a baby girl on Thursday. https://t.co/Gmc92bMknfpic.twitter.com/WLQZkQYTAb
"Congratulations to New Zealand Prime Minister Jacinda Ardern who has given birth to a healthy baby girl! We wish you and your partner all the best."
Congratulations to New Zealand Prime Minster Jacinda Ardern who has given birth to a healthy baby girl! We wish you and your partner all the best. ❤️ #9Todayhttps://t.co/eTxq0vTg5g