The Queen has made a rare personal address to both houses of the British parliament in Westminster Hall to mark 60 years on the throne.
The monarch said she is rededicating herself to the service of the United Kingdom and its people as she celebrates her Diamond Jubilee.
The 85-year-old made it clear she has every intention of carrying on, saying the milestone is a reminder of the country's past, the BBC reports.
"I have been privileged to witness some of that history and, with the support of my family, rededicate myself to the service of our great country and its people - now and in the years to come."
She said the commemoration of her 60 years on the throne was a chance "to come together in a spirit of neighbourliness and celebration".
Hundreds of dignitaries, including Prime Minister David Cameron, his deputy Nick Clegg, Labour leader Ed Miliband and Archbishop of Canterbury Dr Rowan Williams, assembled for the speech in London, which was greeted with a standing ovation.
The Queen paid tribute to the British virtues of "resilience, ingenuity and tolerance", and to her husband Prince Phillip, the Duke of Edinburgh, whom she called her "constant strength and guide" over the decades.
She also looked back at the only other monarch to celebrate a Diamond Jubilee, Queen Victoria, in 1897.
"So, in an era when the regular, worthy rhythm of life is less eye-catching than doing something extraordinary, I am reassured that I am merely the second sovereign to celebrate a Diamond Jubilee."
During the event, a Diamond Jubilee window, a gift from the members of both Houses, was presented to the Queen.
Members of the Royal Family have begun touring the Commonwealth to mark the Diamond Jubilee, with Prince Harry recently returning from a trip to Belize, the Bahamas and Jamaica.
The heir to the throne, Prince Charles and his wife Camilla, the Duchess of Cornwall, will visit New Zealand in November.
