Transcript for Prince Philip will retire from royal duties this fall

Rob mar sciano with us tonight. From London overnight, news of an emergency meeting at Buckingham palace, causing alarm and speculation. Reporters quickly like up outside the palace, getting word that prince Phillip has decided to retire. What's behind the decision? Here's ABC's Terry Moran. Reporter: For seven decades, he has been at her side -- ??? ever-present, ever-loyal. And now at 95, prince Philip will step aside, come this fall, declining all but the most important public appearances. But this afternoon, he hinted why in a typically blunt quip. I was sorry to hear you're standing down. I can't stand up much! Reporter: Philip has stood up, done his duty, to a staggering degree over these 69 years, 22,000 public engagements on behalf of her majesty. They were young Royals when she began her reign, a storybook couple, popular around the world. But it was a tough position for a proud former officer in the royal Navy, as the hit series "The crown" shows. Are you my wife or my queen? I'm both! I want to be married to my wife. Reporter: And this unforgettable moment, Philip supporting his son prince Charles and grandsons William and Harry in that long, awful walk the day princess Diana was laid to rest. Through it all, he has been steadfast. Defining the job succintly. Helping her, supporting her, and doing anything that is valuable to her. Reporter: For the queen. He's been my strength all these years. Reporter: He remains in good health. This is a time of transition. Queen Elizabeth is slowing down a bit and the next generation is taking up more of the royal responsibilities. David. Terry Moran with us, from London.

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