A diplomatic gaffe happened during King Charles and Queen Camilla’s visit to Arlington National Cemetery during their visit to the United States.

After saying farewell to President Donald Trump and first lady Melania Trump on April 30, the King, 77, and Queen, 78, visited the military cemetery in Arlington, Virginia, to pay their respects at one of the country’s most significant sites of military remembrance.

There, the royals laid a wreath and posy at the Tomb of the Unknown Soldier to honor the fallen and the military partnership between the United Kingdom and the United States, but a problem was spotted with the Union Jack flag on parade.

The national flag of the U.K. featured in the King and Queen’s escort was flown upside down.

King Charles III and Queen Camilla pay their respects at the Tomb of the Unknown Soldier in Arlington National Cemetery on April 30, 2026, in Arlington, Virginia.

King Charles and Queen Camilla pay their respects at the Tomb of the Unknown Soldier in Arlington National Cemetery on April 30, 2026.Saul Loeb – Pool/Getty

Britain’s Flag Institute explains that there is a correct way to raise the national emblem. To fly the Union Jack in the proper position, “in the half of the flag nearest the flagpole, the wider diagonal white stripe must be above the red diagonal stripe, as Scotland’s St. Andrew’s Cross takes precedence over Ireland’s St. Patrick’s Cross.”

“It is most improper to fly the flag upside down,” the institute says.

The Union Jack, also called the Union Flag, unites the heraldic crosses of the kingdoms of England and Wales, Scotland and Ireland, where King Charles reigns, though only Northern Ireland has been part of the U.K. since 1921.

Union Jack, Right Side Up, Upside Down

Union Jack flag displayed correctly (left) and incorrectly (right).Mike Kemp/In Pictures via Getty; SAUL LOEB / POOL / AFP via Getty

The flag mishap was the second such snafu to make waves during King Charles and Queen Camilla’s state visit to the U.S. this week to commemorate America’s 250th anniversary of independence.

On April 24, the Friday before the trip kicked off, ABC News reporter James Longman said that Australian flags were briefly raised alongside American flags on the light posts lining a major thoroughfare of Washington, D.C., the King and Queen’s first major stop stateside.

“For about two hours, they put the Australian flag up alongside the Stars and Stripes… I think they realized their mistake, and they’ve replaced them now with the Union Jack,” Longman said in a video shared to Instagram.

The Washington Examiner reported that the Australian flags were erroneously installed along part of 17th Street NW near the Eisenhower Executive Office Building, home to a majority of offices for White House staff, and that an official said the mistake was “quickly” fixed.

Local DC government workers replace the Australian flag with the Union Jack along 17th Street next to the White House on April 24, 2026 in Washington, DC. The DC government mistakenly placed both flags around the White House in preparation of King Charles visit to Washington on April 27, 2026.

Government workers replace the Australian flag with the Union Jack along 17th Street next to the White House on April 24, 2026 in Washington, D.C.Andrew Leyden/Getty

“We posted those flags, but it was quickly rectified, and we were able to remove them,” an official with the D.C. Department of Transportation told the outlet, which added that officials are reviewing how the incident occurred.

The Australian flag features the Union Jack in its upper hoist, nodding to its Commonwealth connection. Australia is one of Britain’s 14 Commonwealth realms and King Charles is also the monarch there.