Social media users called out Ivanka Trump for failing to place her right hand over her heart at the state banquet on Monday. (Photo: YouTube)

Words: Hope Schreiber

While many were gushing about Ivanka Trump's outfit choice at the state banquet at Buckingham Palace on Monday, eagle-eyed social media users noticed a patriotic faux pas.

The First Daughter didn't place her right hand over her heart while the United State's national anthem was played.

Trump, 37, was attending the event as the guest of Queen Elizabeth who’s hosting President Donald Trump and various members of his family and administration, when she failed to show proper etiquette during the playing of "The Star-Spangled Banner."

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According to the Flag Code, when the national anthem is played, "all present except those in uniform should stand at attention facing the flag with the right hand over the heart."

Despite the Flag Code never actually being enforced, and there is no punishment for not abiding by it, many on social media called out the president's daughter for failing to cover her heart.

Why didn't you put your hand on your heart during the Star Spangled Banner in the UK? Your father did. — Ellen Powers (@EllenPo94676126) June 3, 2019

Way to be patriotic @IvankaTrump put your hand on your heart! That was the US’a national anthem not England’s! — The Big J.C. (@TheRealBigJC) June 3, 2019

Shame on Ivanka Trump for not placing her hand over her heart during the State dinner with Queen Elizabeth!!! Another great representative of our country. Another disrespectful person. Shame. — Paula Meyers (@MeyersPaula) June 3, 2019

Well the camera didn’t stay on @IvankaTrump long because she didn’t have her hand over her heart during the National Anthem. There’s no end to the embarrassment the Trump family brings to this Country! Smdh — Marianne (@MarianneSmith7) June 3, 2019

The incident is reminiscent of a similar blunder made by the president in April 2017. During the White House Egg Roll, President Trump was filmed not covering his heart with his hand while the anthem was played.

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His wife, Melania Trump, helpfully nudged him to remind him to place his hand on his heart.

The subtle nudge from Melania reminding Trump to put his hand over his heart for the National Anthem pic.twitter.com/iswL9YMVWv — Lis Power (@LisPower1) April 17, 2017

During the 2008 election campaign, President Barack Obama also fell victim to not knowing the code. The then-senator explained, "My grandfather taught me when I was two. During the Pledge of Allegiance, you put your hand over your heart. During the national anthem, you sing."