US President Donald Trump has arrived in the UK with First Lady Melania Trump, for their highly-anticipated three-day visit.
Stepping off the Marine One helicopter, the President and First Lady were greeted by the Prince of Wales and Duchess of Cornwall, on the grounds of Buckingham Palace.
The pair were then escorted to meet the Queen.
As expected, President Trump was slammed online only a few hours into his trip, for now bowing to Her Majesty. In true Donald fashion, he instead went for a handshake, that looked more like a fist bump.
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"Did...did that man just fist-bump our Sovereign? Get him on the block," one person wrote on Twitter.
While it was a horrifying act to witness by royal fans, there is actually "no obligatory codes of behaviour when meeting the Queen or a member of the royal family, but many people wish to observe the traditional forms."
According to guideline notes posted on the royal family's official website: "For men, this is a neck bow (from the head only) whilst women do a small curtsy. Other people prefer simply to shake hands in the usual way."