Barack Obama Pays Tribute to 'Remarkable' Prince Philip as He Reflects on Their First Meeting

Barack Obama is honoring the life and legacy of Prince Philip, who died on Friday morning at age 99.

The former president, 59, posted a tribute to the Duke of Edinburgh on Instagram on Friday that included a photo of the pair alongside their wives, former First Lady Michelle Obama and Queen Elizabeth, respectively, during Obama's time in office.

In his statement, President Obama reflected on Philip (who retired from his public duties in August 2017) and the Queen's "grace and generosity" during the first meeting between the couples.

"When we first met His Royal Highness Prince Philip, Duke of Edinburgh, he and Her Majesty Queen Elizabeth II had already been on the world stage for more than half a century — welcoming leaders like Churchill and Kennedy; Mandela and Gorbachev," Obama said. "As two Americans unaccustomed to palaces and pomp, we didn't know what to expect."

JOHN STILLWELL/AFP via Getty Queen Elizabeth II, US President Barack Obama, US First Lady Michelle Obama and Prince Philip

"We shouldn't have worried," he added. "The Queen and Prince Philip immediately put us at ease with their grace and generosity, turning a ceremonial occasion into something far more natural, even comfortable. Prince Philip in particular was kind and warm, with a sharp wit and unfailing good humor. It was our first introduction to the man behind the title, and in the years since, our admiration for him has only grown. We will miss him dearly."

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Anwar Hussein/WireImage

The 44th president went on to say that Philip, like his wife, 94, "saw world wars and economic crises come and go. The radio gave way to the television, and the television to the internet. And through it all, he helped provide steady leadership and guiding wisdom."

"It has long been said that the United States and Great Britain have a special relationship — one that has been maintained and strengthened not just by presidents and prime ministers but by the Royal Family that has outlasted them all," Obama wrote.

"At the Queen's side or trailing the customary two steps behind, Prince Philip showed the world what it meant to be a supportive husband to a powerful woman," he continued. "Yet he also found a way to lead without demanding the spotlight — serving in combat in World War II, commanding a frigate in the Royal Navy, and tirelessly touring the world to champion British industry and excellence. Through his extraordinary example, he proved that true partnership has room for both ambition and selflessness — all in service of something greater."

"As the world mourns his loss," Obama added, "we send our warmest wishes and deepest sympathies to the Queen, their children, grandchildren, and great-grandchildren; and everyone who knew and loved this remarkable man."

Anwar Hussein/Getty Barack Obama (left) and Prince Phillip

Along with Obama, world leaders like President Joe Biden, U.K. Prime Minister Boris Johnson, Australian Prime Minister Scott Morrison, Irish Minister for Foreign Affairs Simon Coveney, Indian Prime Minister Narendra Modi, Prince Albert of Monaco and more honored Philip's memory on social media.

Former President Donald Trump likewise issued a statement, saying in part: "Melania and I send our deepest and most profound condolences to Her Majesty Queen Elizabeth II, and to the entire Royal Family. We send our most heartfelt sympathies to the British people. This is an irreplaceable loss for Great Britain, and for all who hold dear our civilization."

Biden told reporters on Friday that Philip lived an "extraordinary life. He's going to be missed."

"Ninety-nine years, he never slowed down," Biden said. "I admired the devil out of him."

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News of Philip's death was announced on Friday.

"It is with deep sorrow that Her Majesty The Queen has announced the death of her beloved husband, His Royal Highness The Prince Philip, Duke of Edinburgh," the palace said in a statement. "His Royal Highness passed away peacefully this morning at Windsor Castle."

The palace continued, "The Royal Family join with people around the world in mourning his loss."

Chris Jackson/Getty Images Queen Elizabeth II and Prince Philip, Duke of Edinburgh

RELATED: Remembering Prince Philip's Life in Photos

For the next eight days, the Queen will refrain from carrying out any royal duties as she enters a mourning period and funeral plans are set in motion. Affairs of state will also be put on pause.

Following the eight days, a further period of official royal mourning is expected to continue. While the country is expected to go into a period of 10 days of mourning, the royal household will do so for 30 days and guardsmen will be seen with black armbands on their tunics during that period.

Philip is survived by the Queen, his wife of 73 years, their daughter Princess Anne and their three sons: next-in-line-to-the-throne Prince Charles, Prince Andrew and Prince Edward.

Philip also leaves behind eight grandchildren, including Prince William and Prince Harry, and nine great-grandchildren, including Prince George, Princess Charlotte, Prince Louis, Archie and Princess Eugenie's new baby boy, August, whose middle name is Philip.