Royal fans have been quick to point out what some believe is a risque detail in the new Coronation portrait of King Charles, which was unveiled at the National Gallery. The King and Queen provided the world with the first glimpse of the two full-length state portraits last week, which will be exhibited for the next six weeks.

Unveiling the works by the artists Peter Kuhfeld who painted Charles, and Paul S. Benney who depicted Camilla, the King praised the “wonderful composition” of his portrait while Camilla said of hers: “I just love it.” However, royal fans think there is a rude detail in King Charles’s portrait.

According to news outlet Joe, one social media user wrote: “Is that a bra thrown on his shoulder?”

Another social media user added: “I thought he had a bra draped over his shoulder?”

Other fans, however, think the Queen’s image was more lifelike than the King’s. They wrote: “Beautiful paintings. In my opinion, the Queen’s painting almost looks a photograph and speaks to me more than the King’s portrait.”

Another said: “The queen’s one is lovely, the Kings one not so much hmm.”

Finding balance in the portraits, one wrote: “Stunning portraits. Very different execution for each but I think each are equally beautiful.”

The portraits form part of a long tradition of coronation portraits dating back centuries, with the earliest known example being a painting of James VI and I by Paul van Somer, which hangs at Windsor Castle.

The King has known the artist Kuhfield for more than 40 years and the artist said it took over a year and a half to complete after the initial sittings at Windsor and St James’s Palace.

The portrait of the King shows him wearing the Robe of State alongside his naval uniform with medals, and the Queen is portrayed wearing her coronation dress. The robe worn by the King is the one used during the first part of the coronation service. In keeping with tradition, alongside him is the Imperial State Crown.