KIRSTY O'CONNOR/POOL/AFP via Getty Catherine, Princess of Wales speaks with First Lady of Ukraine, Olena Zelenska, during a meeting at Buckingham Palace on September 18
The Princess of Wales, 40, and the wife of Ukrainian President Volodymyr Zelensky appeared deep in conversation in a photo that was released following their private meeting.
Zelenska, 44, is set to attend the Queen's funeral on Monday on behalf of Ukraine. She is among 500 dignitaries and world leaders who have traveled to London to pay their respects to the late monarch at her funeral.
President Zelensky, who has been praised by members of the royal family for his leadership amid Russia's invasion of Ukraine, is understood to remain in Ukraine. Russian President Vladimir Putin was reportedly not invited to Queen Elizabeth's funeral.
Kate and her husband Prince William have previously said they "stand" with "all of Ukraine's people."
Stefan Rousseau - WPA Pool/Getty Kate Middleton attend a lunch held for governors-general of the Commonwealth nations at Buckingham Palace on September 17
In April, the royal couple visited the headquarters of the Disaster Emergency Committee in London to learn more about their work to support people affected by Russia's invasion of Ukraine.
In March, the Duke and Duchess of Cambridge made a surprise visit to the Ukrainian Cultural Centre in London to hear about the efforts being made to support Ukrainians in the U.K. and across Europe. They met with members of the Ukrainian community and volunteers to learn about services being offered at the center as well as the challenges they continue to face.
They also brought homemade chocolate brownies and granola bars from Kensington Palace for the volunteers.
Dan Kitwood/Getty Prince William and Kate Middleton
"In October 2020 we had the privilege to meet President Zelenskyy and the First Lady to learn of their hope and optimism for Ukraine's future," the statement from the couple said. "Today we stand with the President and all of Ukraine's people as they bravely fight for that future."
Chris Jackson/Getty Images Prince William and Kate Middleton
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The death of Queen Elizabeth brought many changes to the royal family, including a shift in the line of succession, which resulted in title changes for many senior royals.
As Kate becomes known as the Princess of Wales, which William's mother, the late Princess Diana, once held, a royal source tells PEOPLE, "the new Princess of Wales appreciates the history associated with this role but will understandably want to look to the future as she creates her own path."