Queen Elizabeth sparked 'serious row' with unusual offer to US President on state visit

King Charles and Queen Camilla are set to host Donald and Melania Trump at Windsor Castle during the American President's state visit to the UK.

It's a continuation of a long-standing tradition; the late Queen Elizabeth II met 13 out of the last 14 sitting US presidents over the course of her 70-year reign. And it seems she had a fondness for one in particular, President Barack Obama.

Obama made his last state visit to the UK in 2016 to coincide with the Queen's 90th birthday. But an unexpected request by the monarch sparked a 'serious row', according to a royal expert.

The then-President and his wife Michelle arrived by helicopter in the grounds of Windsor Castle, where they were met in person by the Queen, wearing a floral headscarf to protect against the wind, and her husband Philip in a casual raincoat.

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The royal couple were there to transport the Obamas to the royal residence. But that in itself was a major issue for the Secret Service.

Royal expert Robert Hardman revealed that 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 told the 'Queens, Kings, and Dastardly Things' podcast. "The president can only be driven around by us.

"This created a real ding dong. I spoke to the US staff that had organised the trip and they said there was a very serious row over which car they (the Obamas) 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.

"Obama flew in and 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.

"Michelle and the Queen were in the back, Philip was at the wheel and Obama was in the front – and off they went, tootling around the Park," the author explained.

In his own memoirs, Obama said that as they got in the car, the late Queen told him: "I'm sure there's some rule about who sits where, but sit wherever you like."

Speaking after the State Visit, the US leader further told the press: "I have to say I have never been driven by a Duke of Edinburgh before and I can report that it was very smooth riding!"