Denzel Washington was left baffled by royal protocol when meeting King Charles because he wasn't sure if he was supposed to shake his hand or not

In video footage published after the event, Denzel can be seen meeting the king and saying: "I didn't know if I was supposed to grab you or not, but it's my pleasure."

He went on to talk to the head of the royal family about his character in the movie, saying: "I'm ... just awful ... I'm a lovely man you'll see. I'm a lovely chap and doing my best."

Charles then told him: "You've been in so many films, it's fantastic."

The king also met Paul Mescal, Pedro Pascal and director Sir Ridley Scott at the premiere, which was held in London's Leicester Square.

He arrived at the event in his state Bentley limousine, and posed for photographers on the red carpet, while wearing a black tuxedo with a bowtie.

Queen Camilla missed the screening after she was recently diagnosed with a "seasonal chest infection".

She was also unable to attend the Remembrance events in London over the weekend. Despite this, Camilla was able to chat to a slew of Hollywood A-Listers at Buckingham Palace prior to the premiere.

She told director Ridley at the event: "I am so sorry I'm not coming tonight. I'd be coughing throughout it."