Queen Elizabeth II hosts Bidens at Windsor Castle

LONDON — They met Friday at the Group of Seven summit, but President Joe Biden and the first lady had an altogether more private meeting with Britain's Queen Elizabeth II on Sunday, at her home in Windsor Castle.

The monarch, 95, received the Bidens for tea at her historic residence, about 30 miles west of London. On arrival they were greeted with an official Guard of Honor military parade, which gave a royal salute and played the American national anthem.

Biden stood next to the queen in the sunshine, wearing his aviator sunglasses, before inspecting the troops in the quadrangle of Windsor Castle, last seen on television during the somber funeral ceremony of her husband, Prince Philip, who died aged 99 in April.

The queen has stoically continued with her official duties since then and met Biden alongside other world leaders and their spouses on Friday at the G-7 summit, by the seaside in Cornwall, southwest England.

There, she amused leaders when she quipped during a photo-call: "Are you supposed to be looking as if you're enjoying yourselves?"

Biden, who first met the queen in 1982 as a Democratic senator for Delaware, said following the meeting that she was “extremely gracious" and that she reminded him of his mother in terms of “the look of her and the generosity.” The president also confirmed that he invited her to visit the White House.

Biden is the 13th serving president the monarch has met. She has met every serving American president since Dwight Eisenhower — except Lyndon Johnson who did not travel to Britain while in office.

As a 25-year-old princess in 1951, she also stayed with President Harry S. Truman and his family in Washington, D.C.

The queen has hosted four other American presidents at Windsor Castle in recent years, including former-President Donald Trump in 2018, who shocked press and palace pundits when he breached royal protocol by walking ahead of the queen, at times blocking her view and giving her his back.

After a state visit in 2019, Trump told Fox News: "There are those that say they have never seen the queen have a better time."

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On arrival to England last week, first lady Jill Biden told reporters that meeting the queen was "an exciting part of the visit for us."

She also undertook a separate engagement with Catherine, Duchess of Cambridge, when the two visited a school on Friday.

Kate told NBC News during the visit that she was looking forward to meeting her new niece, Lilibet Diana, born in California earlier this month.

Britain's royal family have had a turbulent year in the public eye following a bombshell interview given by the queen's grandson Prince Harry and his wife, Meghan, the Duchess of Sussex.

The couple stunned viewers with allegations of royal racism — denied by the palace — while Meghan also spoke publicly about how royal life and media pressure had taken its toll on her mental health.

After taking private afternoon tea with the queen on Sunday, Biden is traveling to nearby Brussels for a NATO summit, before heading to Switzerland on Wednesday for a meeting with Russian President Vladimir Putin.

Biden noted the queen asked about Putin and China's President Xi Jinping.