Biden meets with Prince William at JFK Library in Boston

The British royals are stateside for the Earthshot Prize Ceremony.

President Joe Biden met with Prince William on Friday in Boston during the royal couple's first visit to the U.S. in eight years.

The two men exchanged pleasantries as they greeted each other, posed for the cameras and exchanged small talk outside the John F. Kennedy Library and Museum.

"Great to see you," Biden, 80, said as he welcomed the 40-year-old Prince of Wales.

"A spectacular setting," Prince William said, referring to the Boston skyline across the harbor from the library. "Where's your top coat?" Biden asked William, as the temperature was in the low 40s.

Enroute to Massachusetts, White House press secretary Karine Jean-Pierre told reporters that Biden looked forward to meeting Prince William at the library, which is where the president earlier this year announced next steps for his "cancer moonshot" initiative to cut the death toll from the disease in half.

"We expect that they will discuss their shared climate goals, prioritization of mental health issues and decreasing the burden of the disease," Jean-Pierre said ahead of the meeting.

Biden was in Boston for a Democratic fundraiser in support of Georgia Democratic Sen. Raphael Warnock, who is running against Republican Herschel Walker in a Senate runoff election next week.

Before Biden's arrival, Prince William received a tour of the library from Ambassador Caroline Kennedy, the late president's daughter.

The Princess of Wales did not attend the meeting with Biden. On Friday, Kate visited Harvard University to meet with researchers at The Center on the Developing Child.

The British royals are stateside for the Earthshot Prize Ceremony, which awards $1 million prizes to winners of projects focused on resolving climate issues by 2030.

"Like President Kennedy, Catherine and I firmly believe that we all have it in ourselves to achieve great things and that human beings have the ability to lead, innovate and problem solve," Prince William said during their first stop outside Boston City Hall.

The trip also included a Celtics basketball game on Wednesday, where the royal couple was seated next to Massachusetts Gov.-elect Maura Healey and Boston Mayor Michelle Wu. On Friday, William will tour the John F. Kennedy Presidential Library with Caroline Kennedy, the late president's daughter.

It's the royal duo's first overseas visit since the passing of Queen Elizabeth II in September, and the first since taking on the royal titles of Prince and Princess of Wales.

An agent in charge of the Diplomatic Security Service's Boston field office, the agency that makes up the royals' protective detail, told ABC News preparations started in September, and have involved 11 law enforcement agencies.

President Biden and first lady Jill Biden traveled to London for Queen Elizabeth's funeral. They commemorated Queen Elizabeth's "history-making reign" after her death, stating she was a "stateswoman of unmatched dignity and constancy who deepened the bedrock Alliance between the United Kingdom and the United States."

The Bidens paid tribute to the queen as her coffin lay in Westminster Hall, and attended King Charles III's reception at Buckingham Palace.

Prior to that, Jill Biden and Kate met during the Group of Seven, or G-7, summit in Cornwall, England. The two women visited a school that works with students who have experienced trauma in their lives.

"Early childhood education is so important to lay the foundation for all of our students," Jill Biden said during the visit, and thanked Kate for inviting her. The princess said it was a "huge honor" to have the U.S. first lady in the United Kingdom.

ABC News' Justin Gomez and Janice McDonald contributed to this report.