US first lady Jill Biden arrives at Westminster Abbey in London on May 6, 2023, for the coronation ceremony of King Charles III of the United Kingdom.
CNN  — 

First lady Dr. Jill Biden attended the coronation of King Charles III of the United Kingdom on Saturday and reflected on the significance of the historic ceremony moments after its conclusion.

“I thought about, really, the importance of traditions, the importance of oath,” Biden said in a phone interview with CNN during her car ride from the coronation at Westminster Abbey in London. “As I sat there, I felt this sense of decorum and civility that binds together people of all nations.”

“You can’t imagine that moment where you actually see the crown being placed on the head of the king and then on the head of the queen. … It’s really surreal to see and experience that moment.”

Biden had tweeted earlier Saturday that it was “an honor to represent the United States on this historic day at Westminster Abbey.”

“The United States and the United Kingdom have a special relationship,” she said.

President Joe Biden, who did not attend the ceremony, congratulated the royal couple in a tweet Saturday, while also highlighting the “enduring friendship” between the two countries, which he called “a source of strength for both our peoples.”

Biden and her granddaughter Finnegan Biden arrive at Westminster Abbey on May 6, 2023, ahead of the coronation ceremony.

The first lady told CNN she was moved by the message of the archbishop of Canterbury, Justin Welby, during the ceremony.

“What he was saying to the people was that really – people of all nations seek hope and joy. And I thought that was such a strong message, because I think that is true, and it’s true for all people everywhere. But I think it was important at this moment that the clergy brought that into this moment in history,” she said.

Biden’s attendance Saturday marked the first time a US first lady had attended a coronation of a British monarch. However, Jacqueline Bouvier reported on the coronation of Queen Elizabeth II in 1953 for the Washington Times-Herald before her marriage to future President John F. Kennedy.

Biden said she spoke with King Charles during a reception at Buckingham Palace on Friday and that the king was looking ahead to meeting with the president at a later date and offered his regards.

The first lady also spoke with Catherine, the princess of Wales, with whom she was photographed Friday evening.

“We were talking as mothers, and about having kids. We’ve all experienced this – you know – having kids in church. … You do anything to keep them quiet. … We just had a good laugh over it. I think it’s common to a lot of us,” she said.

Biden has met with members of the royal family multiple times as first lady, including on a September 2022 trip to attend the funeral of Queen Elizabeth II, a meeting with the queen alongside President Biden at Windsor Castle in June 2021, and a visit with the now-princess of Wales in Cornwall during the G7 Summit, also in June 2021.

On Saturday, Biden was seated next to Olena Zelenska, the wife of Ukrainian President Volodymyr Zelensky, during the pomp and pageantry at Westminster Abbey.

“I sat next to her today, and we were talking about the war, and she was saying how, really, the sirens are now just commonplace every day. It’s a big part of her life,” she said, adding that Zelenska thanked the US for supporting Ukraine.

Biden said she was looking forward to high tea Saturday afternoon with her granddaughter Finnegan Biden, who joined her on the three-day trip. Later in the day, she will attend a private reception hosted by the US ambassador to the United Kingdom, Jane Hartley. And on Sunday, Biden will attend a “Coronation Big Lunch” hosted by UK Prime Minister Rishi Sunak before returning to Washington.

Akshata Murty, wife of UK Prime Minster Rishi Sunak, welcomes  Biden to 10 Downing Street on May 5, 2023.

On Friday, she met with Sunak’s wife, Akshata Murty, at 10 Downing Street. Together, they visited with members of a nonprofit that provides boxing training and employment support to veterans. They then visited a primary school, where coronation festivities were fully underway.

“It was so meaningful to me that I could bring Finnegan here, that we could travel together and experience this together. And it meant a lot to both of us,” the first lady told CNN on Saturday.

While the president did not attend the coronation – US officials have noted that no previous US president has attended a British monarch’s coronation – he told MSNBC in an interview that aired Friday that he had spoken to King Charles ahead of the ceremony

The president said he told the king that he may visit the UK in July while he is in Europe for a NATO summit and hopes to discuss environmental issues – a cause the monarch is passionate about.

Last month, King Charles extended an invitation to the president to come to the United Kingdom for an official state visit, and he accepted, White House press secretary Karine Jean-Pierre said at the time. 

This story has been updated with additional information.

CNN’s Donald Judd, Kaanita Iyer and Sydney Kashiwagi contributed to this report.