Royal Expert Reveals Why a "Serious Row" Erupted When Queen Elizabeth Offered to Personally Greet Barack Obama in Windsor During U.K. Visit

King Charles and Queen Camilla are set to host Donald and Melania Trump during their presidential state visit to the U.K. this week. Throughout her time on the throne, Queen Elizabeth II met a plethora of American presidents, and she appears to have developed a soft spot for Barack Obama. However, his final state visit to the U.K. in 2016, which coincided with the monarch's 90th birthday, apparently caused an argument to erupt.

During an episode of the Daily Mail's "Queens, Kings, and Dastardly Things" podcast, royal expert Robert Hardman revealed that the late monarch wanted to "pop out" and meet the Obamas in her own vehicle upon their arrival. Unsurprisingly, the Secret Service agents tasked with protecting the president were reportedly displeased with the idea.

According to Hardman, Queen Elizabeth's casual suggestion caused a "very serious row" to start between the Secret Service and Buckingham Palace. "The Secret Service said absolutely no way is that happening," the royal biographer explained. "The president can only be driven around by us."

Hardman further revealed that Obama's staff had "said there was a very serious row over which car they were going to go in and who was going to drive it." He continued, "This dilemma went right the way up to Obama himself, who had to decide. He thought, well it obviously means quite a lot to them, so I'll go in their car."

According to the royal expert, Obama had the final say in how he traveled to Windsor Castle. "For the only time in his entire presidency, he and the First Lady were driven, not in a bullet-proof, bomb-proof whatever, but in a Range Rover driven by Prince Philip," Hardman shared.

Clearly, the Obamas put a lot of faith in the British Royal Family.