Former First Lady Michelle Obama warmly wrapped her arm around the monarch during a 2009 reception at Buckingham Palace

While attending a state banquet at Buckingham Palace on Monday, President Donald Trump put his hand on Queen Elizabeth‘s back, sparking debate on whether or not he broke royal protocol.

The incident took place after Trump, 72, praised the Queen, 93, as a “great woman” for her work during World War II.

“From the Second World War to today, her majesty has stood as a constant symbol of these priceless traditions,” Trump said of the Queen at the dinner.

“She has embodied the spirit of dignity, duty and patriotism that beats proudly in every British heart,” he added.

The Queen also spoke of her respect for the U.S. saying in her speech, “Tonight we celebrate an alliance that has helped us to ensure the safety and prosperity of both our peoples for decades, and which I believe will endure for many years to come.”

In response to the back-patting gesture, the Queen didn’t appear ruffled.

The royal family’s website states, “There are no obligatory codes of behavior when meeting The Queen or a member of the Royal Family, but many people wish to observe the traditional forms.”

Screen Shot 2019-06-03 at 6.51.17 PM
Donald Trump and Queen Elizabeth

If an individual wishes to observe the traditional forms, it is advised that men perform a “neck bow (from the head only)” while women do a “small curtsy.”

“Other people prefer simply to shake hands in the usual way,” the website states.

In addition, the Queen should be addressed as “Your Majesty” upon presentation, and subsequently as “Ma’am.”

Former First Lady Michelle Obama warmly wrapped her arm around the Queen during a 2009 reception at Buckingham Palace.

The Queen responded by putting her own arm around the first lady’s waist.

Donald Trump and Queen Elizabeth

Obama, 55, later commented on the incident in her book Becoming, writing, “If I hadn’t done the proper thing at Buckingham Palace, I had at least done the human thing.”

“I daresay that the Queen was okay with it, too, because when I touched her, she only pulled closer, resting a gloved hand lightly on the small of my back,” she added.

Following Trump’s visit with the Queen, he and First Lady Melania Trump will head to Ireland on Wednesday and then to France on Thursday.

G20 leaders attend a reception at Buckingham Palace, London, Britain - 01 Apr 2009
Michelle Obama and Queen Elizabeth
| Credit: REX/Shutterstock

The four-day European trip’s official purpose, per the White House, is to commemorate the 75th anniversary of D-Day while reaffirming the close alliance between the U.S. and the U.K. The itinerary includes a mix of ceremonial occasions, including the banquet at Buckingham Palace, and political engagements, such as meeting with departing U.K. Prime Minister Theresa May.

The president is a divisive figure in the U.K., and he has continued to stir controversy even as he arrived on Monday morning. As he was landing in London, he attacked the city’s Mayor, Sadiq Khan, in a tweet, calling him “stone cold loser,” and last week, he said Meghan Markle‘s criticism of him as a presidential candidate was “nasty.”