The BBC has released a new clip of its latest royal documentary which is set to be broadcast tonight showing the sweet moment King Charles embraces his grandchildren during the Coronation rehearsals.

In the new clip, Prince William and Princess Kate can be seen arriving at Westminster Abbey along with their children Prince George, Princess Charlotte and Prince Louis.

At one point, the Bishop of Hereford, Richard Jackson can be heard saying: “I think what struck me particularly, is how extraordinarily affectionate they are.

“They’re clearly a very close family, all the generations, and essentially it felt like you’re part of a family occasion as well as a royal and a national occasion.”

The clip then shows King Charles kissing his son William and his wife Kate before warmly hugging each of his grandchildren.

The new documentary will show never-before-seen footage of Charles and Queen Camilla in the first year of the monarch’s reign.

In other clips released last week, Prince George can be seen wearing his red uniform and fixing his gloves as his grandfather and Queen Camilla get in the Diamond Jubilee State Coach to travel from Buckingham Palace to Westminster Abbey.

The monarch can also be seen lifting the arm in his robe and saying “I can fly” before gesturing to his four pages, including George, “Shall we get ourselves organised round there?”

In another moment, Queen Camilla’s sister, Annabel Elliot, who was a “Queen’s Companion” at the event, can be seen looking tearful as she watches her sister head to Westminster Abbey to be crowned Queen.

Another clip showed King Charles laughing after the Archbishop of Canterbury Justin Welby could not remember his lines during a rehearsal for the Coronation.

Princess Kate can also be seen kissing her father-in-law after curtsying following the Coronation ceremony.

BBC’s 90-minute documentary Charles III: The Coronation Year will be screened on tonight at 6.50pm on BBC One and iPlayer.