Queen Elizabeth updates: State funeral ends 11 days of ceremonies

In his first speech as monarch, King Charles III pledged to follow in the footsteps of Queen Elizabeth II, upholding Britain's Constitution.

"As the queen herself did with such unswerving devotion, I too now solemnly pledge myself throughout the remaining time God grants me, to uphold the constitutional principles at the heart of our nation," King Charles III said.

"And, wherever you may live in the United Kingdom, or in the realms and territories across the world, and whatever may be your background or beliefs, I shall endeavor to serve you with loyalty, respect and love as I have throughout my life."

The king also recognized his new role, and the changes it will bring.

"My life will, of course, change as I take up my new responsibilities. It will no longer be possible for me to give so much of my time and energies to the charities and issues for which I care so deeply. But, I know this important work will go on in the trusted hands of others," the king later said.

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King Charles III addresses UK and commonwealthThe address is King Charles III's first as the monarch.

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King Charles III announced new titles for his son, Prince William, and his son's wife, Catherine, the Duke and Duchess of Cambridge.

They are now the new prince and princess of Wales, the new king announced in a speech from Buckingham Palace Friday.

"Our new prince and princess of Wales will, I know, continue to inspire and lead our national conversations," King Charles said in the prerecorded message.

William's mother, Diana, was the last Princess of Wales. Charles' wife, Camilla, never took the title. With Charles' accession, her title is now queen consort.

King Charles also mentioned his younger son, Prince Harry, and his wife, Meghan, the Duke and Duchess of Sussex.

"I want also to express my love for Harry and Meghan, as they continue to build their lives overseas," the king said.

In his first address, King Charles III ended his address thanking his mother, Queen Elizabeth II, for her lifetime of service and her love and devotion.

"To my darling mama, as you begin your gray last journey to join my dear late papa, I want simply to say this. Thank you. Thank you for your love and devotion to our family, and to the family of nations you have served so diligently all these years," King Charles III said.

The king also expressed his gratitude for the "condolences and support" that his family has received after the passing of the queen.

King Charles III delivered his first address as monarch Friday, in remembrance of his mother, Queen Elizabeth II, saying her death has brought him "profound sorrow" and "great sadness."

"Throughout her life, her majesty, the queen, my beloved mother, was an inspiration. An example to me and to all my family. And we owe her the most heartfelt debt any family could owe to their mother for her love, affection, guidance, understanding and example," King Charles said.

The king said the queen's affection, admiration and respect were a hallmark of her reign.

"I pay tribute to my mother's memory and I honor her service," he later added.