Even royals aren’t immune to the nerves that come with meeting a U.S. president.

The correspondence was written after Philip visited the White House solo, withoutQueen Elizabeth, for a dinner hosted in his honor.

From left: Bebe Rebozo, Prince Philip and Richard Nixon.Nixon Presidential Library

Prince Philip, Richard Nixon

The letter continues: “After the brilliance of the other speakers and yourself, I am afraid my contribution was very lame and that night I woke up in a cold sweat when I realized I had forgotten to propose your health! I do humbly apologize.”

From left: Queen Elizabeth, Prince Philip, Richard Nixon.Nixon Presidential Library

Prince Philip, Richard Nixon

Nixon Presidential Library

Prince Philip, Richard Nixon

“I hope we did a good piece,” the prince writes. “Again with very many thanks for your great kindness. Yours sincerely, Philip.”

The Miss Walters mentioned is Barbara Walters, whointerviewed Philipduring his stay in New York. That interview lifted the curtain on life in the Queen’s shadow, which Philip told Walters at the time was “awkward.”

“You get used to anything,” he told Walters when asked if he had settled into the role. “You’d be surprised.”

Philip’s path crossed with the Nixons on more than one occasion.

In 1957, Nixon, then vice president, and his wifewelcomedboth the Queen andPrince Philipto the U.S. Capitol on behalf of President Dwight Eisenhower. A decade later, in February 1969, then-President Nixon visited the Queen and Philip at Buckingham Palace and, the following year, the two couples met again in England at the U.K. prime minister’s country residence.

Nixon reportedly had a special interest in the royal family, withPrince Charleslater saying the president had attempted toset him upwith first daughter Tricia Nixon.

RELATED VIDEO:Prince CharlesGets Emotional as He Views Public Tributes to FatherPrince Philipwith Camilla

Prince Philip, Richard Nixon

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Philip’s humor stayed with him “right to the end,” according to former palace spokeswoman Ailsa Anderson, who recently told PEOPLE that the Duke of Edinburgh was “charming,” with a “twinkle in his eye.”

“When he spoke to you, you thought you were the only person who mattered in the world,” Anderson said in PEOPLE’s cover story. “It was like a lighthouse beacon shining onto you, and you feel like the only person he wanted to talk to.”

Philip is set to be laid to rest at St. George’s Chapel in Windsor Castle on Saturday amid strict COVID-19 guidelines.

According to Anderson, it’s what the late prince would have wanted, even without the pandemic.

“Ironically, it is probably how he would have liked,” she told PEOPLE. “No fuss, no bother. Right through his life, he never knew what all the fuss was about.”

source: people.com