Catherine, Princess of Wales has made her first public appearance since completing chemotherapy

Catherine was seen in photographs published by The Sun flashing a brief smile as she sat in the passenger seat of a car beside William, who was driving their vehicle.

She was wearing a dark green wide-brimmed hat with feathers on the side and a brown tartan checked coat, while William wore a dark suit for the event.

King Charles, 75, who is still fighting an undisclosed form of cancer, and his wife Queen Camilla, 77, were also seen going into the church in separate cars.

Catherine's appearance is her first since announcing earlier this month that she finished her chemotherapy treatment, which she first revealed she was undergoing in March.

The princess, who has children Prince George, 11, Princess Charlotte, nine, and six-year-old Prince Louis with William said in her statement on finishing her preventative cancer treatment it was a "relief" to have completed it.

She added: "The last nine months have been incredibly tough for us as a family. Life as you know it can change in an instant and we have had to find a way to navigate the stormy waters and road unknown.

"The cancer journey is complex, scary and unpredictable for everyone, especially those closest to you... this time has above all reminded William and me to reflect and be grateful for the simple yet important things in life, which so many of us often take for granted. Of simply loving and being loved."