Mark Zuckerberg has revealed he plans to give away 99% of his $45bn Facebook fortune as he announced the birth of his first child.

"Priscilla and I are so happy to welcome our daughter Max into this world!" Zuckerberg posted on his Facebook page on Tuesday.

The new dad then went on reveal plans to give away the vast majority of his Facebook shares, currently $45bn, during his lifetime "to join many others in improving this world for the next generation".

He wrote: "We are committed to doing our small part to help create this world for all children."

Zuckerberg, 31, linked his post to a letter addressed to his daughter, in which he and Priscilla wrote about the world they hope Max grows up in.

"We will do our part to make this happen, not only because we love you, but also because we have a moral responsibility to all children in the next generation," the letter said.

It goes on to lay out a mission of combating disease around the world, advancing human potential and promoting equality.

"We will give 99% of our Facebook shares - currently about $45 billion - during our lives to advance this mission," he wrote.