Transcript for Countdown begins for Prince Harry and Meghan Markle's wedding

about the royal wedding. One of the outtakes now making he headlines from the interview 24 hours ago. Here's ter Moran. Reporter: For Harry and Meghan, the countdown has begun. A may wedding at St. George's chapel at Windsor castle, the queen's primary residence. And the royal family will pay for the festivities. The royal relatives weighing in today, Harry's sister-in-law Kate, the duchess of Cambridge. William and I are absolutely thrilled. It's such exciting news. It's a really happy time for any couple, and we wish them all the best, and hope they enjoy this happy moment. Reporter: And Camilla, prince Charles' wife. As I said, America's loss is our gain. Reporter: And the public welcoming their soon-to-be American princess. It's good to see the royal family moving with the times at last. It's time he got married and settled down. Reporter: During that interview, they just seemed so in love. The tabloids even turning to a lip reader to see just what the couple is whispering during those off-mike moments. Harry and Meghan laughing. Interrupting each other. "She wants me to say something," Harry says here. "Oh, sorry," Meghan apologizes, and gives him a look that slays. Terry, we're learning Markle will become a British citizen. Does that mean she gives up her U.S. Citizenship? Reporter: There's no law that would require it. As an American citizen, she's still subject to U.S. Tax law. And the British royal family may just not like that. Terry, thanks. There's still much more ahead on "World news tonight"

This transcript has been automatically generated and may not be 100% accurate.