Prince Harry says his father did not hesitate to step in after the Duchess of Sussex's father pulled out of walking her down the aisle in May.
Thomas Markle decided not to travel from his Mexico home after being humiliatingly exposed for colluding with a paparazzi photographer in the run-up to the nuptials.
When it became clear that Meghan wouldn't have her reclusive father to support her, Harry went to his, according to the Daily Mail.
Speaking in a documentary to mark Charles' 70th birthday, Harry says: "I asked him to and I think he knew it was coming and he immediately said "Yes, of course, I'll do whatever Meghan needs, and I'm here to support you".
"For him that's a fantastic opportunity to step up and be that support, and you know he's our father so of course he's going to be there for us. I was very grateful for him to be able to do that."
Millions of viewers were left deeply moved as the prince turned to his father and said, "Thank you Pa", as Charles completed the walk down St George's Chapel at Windsor with Meghan on his arm.
Charles's wife, the Duchess of Cornwall, says: "That was very touching. But afterwards watching it on the television, I think it was a lovely gesture."
Prince William insists he wants to take his own path in life.
The second in line to the throne says: "There are so many things I admire about my father – his work ethic, his passions ... but personally I want to be my own man and take my own style, my own passions and my own interests my way, and do things slightly differently.
"It's important that each generation does things a little bit differently."