The newly appointed British prime minister mourned the death of Queen Elizabeth II in a speech made outside Number 10 Downing Street, offering her condolences to the royal family and "loyalty and devotion" to the new monarch - the queen's son, King Charles III.

"We are all devastated," Liz Truss began late Thursday afternoon after the announcement of the monarch's death.

Describing the death of Queen Elizabeth II as "a huge shock to the nation and the world," Liz Truss also paid tribute to Elizabeth II's nearly seven-decade reign, stating that the monarch outlined the path for modern-day Britain, looking back on her reign as "a life of service that extends beyond our memory in life."

"The UK is the country it is now because of the Queen," said Liz Truss quoted by the Economic newspaper.

The ruler left her condolences to the royal family, and especially to the new monarch, King Charles III: "We mourn the death of your mother.

Now is the time to "unite as a nation in support of the king," he declared, promising to offer him "loyalty and devotion."

"With the passing of the second Elizabethan era, we are now moving into a new era in our great country, exactly as his majesty would wish, as we acclaim the words, God Bless the King," Liz Truss concluded.