The Danish royal attended the game with his daughter, Princess Isabella 
The Prince of Wales was seen enjoying a playful moment of banter with Denmark's monarch
The UK and Denmark's royals shared a friendly rivalry as they turned out to watch their respective teams play, according to a body language expert.
The Prince of Wales was seen enjoying a playful moment of banter with Denmark's monarch, King Frederik, at the Euros match in Frankfurt on Thursday. Although the match itself lacked excitement, William's enthusiasm for being a football fan for the night was evident, expert Judi James noted.
The 41-year-old Prince engaged in lively conversation with the new king Frederik, who ascended the throne earlier this year after the unexpected abdication of his mother, Queen Margarethe, in January. The Danish royal attended the game with his daughter, Princess Isabella.
Meanwhile, William represented his family alone, as Kate, currently undergoing cancer treatment, and their children, who are still in school in England, did not accompany him. William posed for pictures with Frederik and Isabella a day before his 42nd birthday, with the two men puffing their chests in a display of friendly rivalry.
Expert Judi James said: "We all know William has a competitive streak but watching him in what looks like a banter-riddled pre-match royal face-off with King Frederik is hilarious. The two royals puff their chests in a splay of superiority and there’s some very animated gesticulation that involves pointing to press home their messages.
"They clearly both love the opportunity to behave like ordinary fans and William’s raised chin and open mouth suggests he feels he might have won the royal battle of the terraces even if England don’t win out there on the pitch."
A picture of the three was shared on X, formerly Twitter, with the caption, "May the best team win". William's appearance came a day after he showed up for a very different sporting event.
The family were out in force with William joining his cousins Zara and her husband Mike Tindall, Princess Beatrice and her husband Edoardo Mapelli Mozzi, and Princess Eugenie and her spouse Jack Brooksbank .
