President TrumpDonald John TrumpWarren unveils Native American policy plan Live-action 'Mulan' star spurs calls for boycott with support of Hong Kong police Don't let other countries unfairly tax America's most innovative companies MORE was mocked on Twitter for his apparently ill-fitting formal wear during a state banquet hosted by Queen Elizabeth II at Buckingham Palace.

Trump attended the lavish feast with first lady Melania TrumpMelania TrumpEx-Melania Trump adviser raised concerns of excessive inauguration spending weeks before events: CNN The Hill's Morning Report - Trump moves green cards, citizenship away from poor, low-skilled White House seeks volunteers, musicians for Christmas celebrations MORE, who was wearing a Dior Haute Couture gown, but Twitter users quickly jumped on the president over his tuxedo tails. 

Actress Bette Midler, a frequent Trump critic, detailed what she called a “proportion fail."

“His white waistcoat is at least two inches too long; tailcoat is supposed to be almost the same length as the waistcoat beneath, sleeves should be shorter and show a bit of the cuff below, waist itself is nipped in...what a figure he cuts! Fire the tailor!!” Midler wrote on Twitter.

MSNBC host Joy Reid asked royal experts on Twitter to weigh in on the length of Trump's vest tails.

Others compared Trump's attire to a similar outfit worn by former President Obama at a state banquet in May 2011, and joked about the fit of Trump's tails. 

Sen. Chris MurphyChristopher (Chris) Scott MurphyOvernight Defense: US, Russia tensions grow over nuclear arms | Highlights from Esper's Asia trip | Trump strikes neutral tone on Hong Kong protests | General orders ethics review of special forces White House eyes September action plan for gun proposals Trump phoned Democratic senator to talk gun control MORE (D-Conn.) even weighed in, saying he was more concerned with Trump’s behavior during the three-day state visit.

“What I care about is how monumentally stupid it is for Trump to be cheerleading Brexit. There is no way to confront an expansionist Russia and a rising China without the United States and a strong, united Europe working together,” Murphy wrote on Twitter.

Trump on Sunday said that he would support the United Kingdom leaving the European Union without a Brexit deal if U.K. officials can't reach an agreement with EU leaders. 

"If they don’t get what they want, I would walk away,” Trump told Britain's Sunday Times just before the state banquet. “Yes, I would walk away. If you don’t get the deal you want, if you don’t get a fair deal, then you walk away.”