Manchester United player Cristiano Ronaldo has announced on social media that his son died during childbirth on Monday.

His partner Georgina Rodríguez was pregnant with twins, a boy and a girl, and Ronaldo said it was only the birth of his daughter and fifth child that provided him the strength “to live this moment”.

“It is with our deepest sadness that we have to announce that our baby boy has passed away,” the 37-year-old posted on Instagram on Tuesday morning AEST.

“It is the greatest pain that any parents can feel. Only the birth of our baby girl gives us the strength to live this moment with some hope and happiness.

“We would like to thank the doctors and nurses for all their expert care and support. We are all devastated at this loss and we kindly ask for privacy at this very difficult time. Our baby boy, you are our angel. We will always love you.”

The pair, who already had four children, announced they were expecting twins in October.

“Delighted to announce we are expecting twins,” they posted at the time.

“Our hearts are full of love — we can’t wait to meet you.”

Rodriguez has previously called Ronaldo the “best dad in the world”.

Manchester United was due to play Liverpool on Tuesday evening but Ronaldo had not yet commented when he’d return to the game.

Manchester United posted a message on Twitter on Tuesday morning: “Your pain is our pain, @Cristiano Sending love and strength to you and the family at this time.”

Image: Instagram / Cristiano Ronaldo