The TalkTV presenter addressed the brothers and their wives reuniting during a sombre occasion, amid claims of tensions between the four royals.
The Virgin Radio host quizzed: “What have you purposefully not talked about Piers, over the last few days? What have you stayed away from?”
Addressing Meghan and Harry reuniting with Kate and William, Piers said: “It was good to see them coming together but I think that it’s been described as more of a truce than a proper peace settlement.
“We know Harry has got this book coming out. How much damage will that book, if it genuinely is what people think it is, a real tough thumping assault of what he has had to endure as a young prince.