He continued: "My two little ones are still at their age of innocence. Sometimes I feel like I can keep them away from the online harm that they could face in the future forever, but I'm learning to know better."
The duke went on to claim social media "isn't working" and hopes his children, Archie and Lilibet "never have to experience it as it exists now".
"No kid should have to," he added.
In 2020, one day prior to quitting the royal family, the duke and duchess deleted their joint Instagram account but later insisted they had not "quit" social media for good only until they see more "meaningful commitments to change or reform".
Last year Prince Harry spoke to Fast Company, admitting he and Meghan will "revisit social media when it feels right for us".
The news comes after the couple announced they will be joining the rest of the royal family in Britain to celebrate the Queen's Platinum Jubilee.
They will also be bringing their children for the four-day celebration in June.
Prince Harry and Meghan's statement was released a mere 18 minutes after the Queen revealed they – along with Prince Andrew – will not appear on the Buckingham Palace balcony.
Queen Elizabeth's statement noted only working members of the royal family will wave to crowds on The Mall during the traditional Trooping the Colour RAF flypast scheduled for June 2.