US President Donald Trump has paid a heartfelt tribute to the Queen.
He praised her "spirit of dignity, duty, and patriotism that beats proudly in every British heart" after he spent the day with the "fantastic" royal family.
After the pomp and pageantry of the ceremonial welcome which clearly impressed the US leader and First Lady Melania Trump, he ended the first day of his state visit by praising the wartime strength of Britain, its people and the monarchy, in a speech delivered during a banquet staged in his honour.
In her address the Queen celebrated the special relationship between the UK and its closest ally, and while Brexit was not mentioned she highlighted how the two countries faced "new challenges of the 21st century".
But the forthcoming 75th anniversary of D-Day - the start of the Second World War liberation of Europe - reminded everyone about British and American achievements since 1944.
The Queen said: "As we face the new challenges of the 21st century, the anniversary of D-Day reminds us of all that our countries have achieved together.
"After the shared sacrifices of the Second World War, Britain and the United States worked with other allies to build an assembly of international institutions, to ensure that the horrors of conflict would never be repeated.
"While the world has changed, we are forever mindful of the original purpose of these structures: nations working together to safeguard a hard-won peace."
Mr Trump told the Buckingham Palace guests, which included DUP Westminster leader Nigel Dodds: "As we honour our shared victory and heritage, we affirm the common values that will unite us long into future.
"Freedom, sovereignty, self-determination, the rule of law and reference for the rights given to us by almighty God.
"From the Second World War to today, Her Majesty has stood as a constant symbol of these priceless traditions.
"She has embodied the spirit of dignity, duty, and patriotism that beats proudly in every British heart.
"On behalf of all Americans, I offer a toast to the eternal friendship of our people, the vitality of our nations and to the long-cherished and truly remarkable reign of Her Majesty, the Queen. Thank you."
As the guests stood up and raised their glasses, Mr Trump appeared to breach accepted royal protocol by touching the Queen on the back.
He briefly and gently put his left hand out behind the monarch who seemed unperturbed.
He also said: "The courage of the United Kingdom's sons and daughters ensured that your destiny would always remain in your own hands. Through it all, the royal family was the resolute face of the commonwealth's unwavering solidarity.
"In April 1945, newspapers featured a picture of the Queen Mother visiting the woman's branch of the Army, watching a young woman repair a military truck engine. That young mechanic was the future Queen, a great, great woman."
Earlier, Mr Trump had posted a series of controversial Twitter messages, launching a tirade against the London Mayor, "fake news" and China.
But after being welcomed by the Prince of Wales and Duchess of Cornwall on the palace lawns before meeting the Queen, having lunch with the monarch and her family, then tea with Charles and Camilla, the President tweeted the trip was "going really well".