Watch: King Charles quotes Shakespeare in first speech as monarch to UK Parliament

King Charles III on Monday addressed Parliament for the first time as Britain's monarch during which he pledged to follow the example of selfless duty set by his "darling late mother" Queen Elizabeth II in upholding "the precious principles of constitutional governance”.

Responding to the condolences offered by the House of Commons and Lords at Westminster Hall in London, the monarch reflected upon the "weight of history" as he pointed to the many symbols of his mother’s reign around the historic Westminster Hall within the Houses of Parliament complex and quoted from William Shakespeare to pay tribute to the Queen, who passed away aged 96 in Scotland on Thursday.

"While very young her late Majesty pledged herself to serve her country and her people and to maintain the precious principles of constitutional government which lie at the heart of our nation,” said Charles.

"This vow she kept with unsurpassed devotion. She set an example of selfless duty which with God's help and your counsels I am resolved faithfully to follow," he said.

Quoting Shakespeare, he noted: "As Shakespeare said of the earlier Queen Elizabeth, she was a pattern to all princes living." In setting the tone for his own relationship with MPs and peers, Charles described Parliament as "the living and breathing instrument of our democracy" and highlighted the “tangible connections to my darling late mother” all around, including the great bell of Big Ben – “one of the most powerful symbols of our nation throughout the world and housed within the Elizabeth Tower also named for my mother’s Diamond Jubilee”.

Around 900 members of Parliament and peers gathered for this stage of the constitutional ritual of State Mourning, as they pledged loyalty to the new sovereign. The Speaker of the House of Commons, Sir Lindsay Hoyle, read out the condolence message, which was then handed to the new monarch.

"Deep as our grief is, we know yours is deeper... There is nothing we can say in the praise of our late Queen, your mother, that you do not already know," said Hoyle.

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