This is an NBC News special report. Here's Savannah Guthrie.

Hello from London, and as we come on the air, we are just moments away from the very

first public address to the nation from King Charles III. A speech he recorded a few

hours ago here at Buckingham Palace, as you can see, surrounded by throngs of mourners.

This set to be broadcast just moments from now. And this was the scene that King returned

to earlier today, as he returned from Scotland, where his mother passed. This afternoon thousands

of mourners outside the palace gates there to pay tribute to Queen Elizabeth, and her

extraordinary 70-year reign, the King and Queen Consort Camilla's stopping as you see there

to meet and greet the crowd and then take a walk to view the ever-growing floral tribute.

At this hour, at St. Paul's Cathedral, a service is underway. The new Prime Minister and

other dignitaries gathering in a service of prayer and reflection. Two thousand members

of the public to attend, tickets first come, first served, it went in hours, and notably

at this service, we will hear the first official rendition of God Save the King. So as we await

the King's address to the nation, let's go to NBC News, Senior International Correspondent

here, Simmons, on this remarkable day here.

Well, Savannah, as the King walked into Buckingham Palace for the first time as King, he went

there to record this first message to his people, and I think that he will try to set a tone

much as his mother did, the Queen, back in 1953 on her coronation. When she said, throughout

my life, and with all my heart, I shall strive to be worthy of your trust. Well, the

King said, must make people convinced that he can lead them, that he can be worthy of

their trust. And at the same time, those pictures of him greeting the people, he is going

to want to connect himself with his people. He has a lot to do, Savannah.

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