Donald Trump breaks major royal etiquette in first moments of meeting with King Charles

Donald Trump is in the UK for his second state visit, and the order of the day is pomp and ceremony in Windsor as he meets King Charles.

There's an awful lot of etiquette to go along with these royal ceremonies and plenty of people will remember that Trump previously made a hash of things by walking in front of the late Queen Elizabeth II.

Now he's back and once again has been breaking the rules, with the US president and his wife showing up late and Trump then breaking protocol as he failed to bow to the King and Queen upon his arrival.

According to royal etiquette when meeting a member of the royal family one is expected to bow, with men performing a neck bow while women are expected to curtsy.

Trump then failed to follow the accepted customs again as he got rather handsy with King Charles, touching him and Prince William repeatedly after a handshake in greeting.

Bow your head, shake the hand if it's offered to you and don't keep touching them, that's the etiquette (IAN VOGLER/POOL/AFP via Getty Images)

It's not part of official protocol not to touch the royals, but generally, you're not supposed to beyond the handshake if one is offered to you.

Observers noticed that Trump also repeated his previous mistake by walking in front of the monarch, with the US president striding off alongside a soldier while the King followed on behind.

Trump's itinerary for the day is lots of ceremony and parades followed by a state banquet at Windsor before he heads off to Chequers tomorrow (18 September) for a meeting with British Prime Minister Sir Keir Starmer.

Security for the state visit is a major concern, as nobody wants anything to go horrendously wrong, and Trump's team has come prepared with a fridge full of blood following him around at all times in case he needs some.

Four people have been arrested for projecting an infamous photo of Trump standing alongside convicted (and deceased) sex offender Jeffrey Epstein onto Windsor Castle.

He's meant to be on his best behaviour for the visit (Kirsty Wigglesworth - WPA Pool/Getty Images)

Meanwhile, the people who enjoy the 'fake Melania' conspiracy theory were enjoying the arrival of the Trumps last night (16 September) into the UK, given that she appeared to be holding his hand.

Observers said it was a 'rare' display of affection for America's first couple, who have so often not appeared to be the picture of love and contentment in their marriage.

People joked that they couldn't tell 'which Melania' this was and remarked that the US president might have a 'public trip stand in Melania'.