President Joe Biden on Monday caused a stir when he appeared to breach royal protocol by touching King Charles III during an arrival ceremony at Windsor Castle, while the King appeared to lose his cool after one of the Welsh Guards at the castle seemed to spend too much time engaging the president in conversation. Mr Biden, who’d arrived in the UK late on Sunday and spent the night at the US Embassy in London, closed out the day’s engagements by meeting with the King and a group of business leaders alongside several US and UK officials. After arriving on the Windsor grounds by helicopter for their first one-on-one meeting since Charles became King last year, Mr Biden raised eyebrows among longtime palace observers by placing his hand on the monarch’s elbow as the two men shook hands. Following that warm greeting, the president placed his hand on the King’s back as they reviewed the assembled Welsh Guards on the Windsor quadrangle, with the monarch reciprocating in a similar gesture a short time later. Both men appeared to be smiling and in good spirits as they ambled about the castle grounds, with Charles attempting to hurry Mr Biden along at one point as they reviewed the Guard of Honour. Mr Biden, who was engaged in conversation with one of the soldiers he was reviewing, failed to heed the monarch’s polite suggestion to keep moving, with the King appearing to snap and gesture at the guard after the president moved along. Although protocol states that the monarch is generally not to be touched, a Buckingham Palace source told People that Mr Biden did not breach protocol and said the King was “entirely comfortable” with the encounter. "What a wonderful symbol of warmth and affection it was between both the individuals and their nations," they said. The King and Mr Biden have met multiple times during their time in public life, with their two most recent meetings coming during the Cop26 summit in Glasgow and a Buckingham Palace reception during the 2021 G7 summit. Both of those times, the subject at hand was their respective efforts to battle climate change, and the same topic was on the agenda during Mr Biden’s visit with the King. Both men participated in what the White House described as a ”climate engagement” featuring His Majesty and a number of “philantrophists and investors,” including the chief executives of Bank of America, Prudential, and BlackRock, as well as US climate envoy John Kerry and Grant Shapps, the British Secretary of State for Energy Security and Net Zero. Mr Shapps told reporters that British officials are “enormously pleased” that the Inflation Reduction Act signed by Mr Biden last year “advanced clean energy goals”. Mr Biden’s audience with the King came immediately following a 42-minute visit to Number 10 Downing Street for tea with Prime Minister Rishi Sunak. As he sat in the back garden with the PM, Mr Biden said the relationship between the US and the United Kingdom continues to be “moving along in a way that is positive” and “rock solid”. The US president, who has met with his British counterpart five times in the last five months, quipped that it was “good to be back” and commented that he and Mr Sunak have “only been meeting once a month”. For his part, the British Prime Minister said he and Mr Biden would use the brief bilateral meeting to discuss “how do we strengthen our cooperation” and “joint economic security to the benefit of our citizens”. “We stand as two of the firmest allies in that alliance and I know we’ll want to do everything we can to strengthen Euro-Atlantic security,” he said. Following the meeting with the King, Mr Biden departed London for Vilnius, where he will participate in the Nato leaders’ summit before travelling to Helsinki for a meeting with Nordic leaders. Read More King and President Biden’s meeting reinforces US-UK special relationship People defend Joe Biden after reporter claims he wore sneakers without socks during trip to UK: ‘Impeach!’ Biden’s biggest gaffes: Muddling up wars, dozing off mid-event and a series of tumbles Budget 2022: Hunt says UK in recession as he announces huge tax rises Jeremy Hunt increases energy windfall tax in budget Jeremy Hunt freezes tax allowances and hits 45p rate payers