King Charles appears in public at Easter Sunday church service

King Charles has greeted well-wishers in his first major public appearance since being diagnosed with cancer.

The King spoke to crowds and shook people's hands after the Easter Sunday service in Windsor, where he was accompanied by Queen Camilla.

The Prince and Princess of Wales did not attend, as Catherine continues her cancer treatment.

One man told the King to "keep going strong". Others said he "looked well" and seemed in "good spirits".

The King has continued some work since his diagnosis, but all engagements so far have taken place in private.

The 75-year-old King surprised waiting crowds, who applauded as he greeted them outside St George's Chapel after the service.

It was a chilly day and he told people: "You're very brave to stand out here in the cold."

Many of the crowd wished the couple a happy Easter and told the King to get well soon.

"We're all rooting for you, we've all got your back," a member of the public told him.

Another man said: "Keep going strong, Your Majesty. Keep going strong, never give in."

The King joked: "I have to obey my instructions."

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The King seemed to enjoy the walkabout and it was a positive sign that he felt able to shake hands and chat to the crowd.

Henry Wood, 20, a private wine merchant from Basingstoke who attended the service inside St George's Chapel with his family, said the King appeared to be "in good spirits".

"Obviously it being his first appearance in quite some time, I think people wanted to see him for that reason," Mr Wood said.

"He looked good today and in high spirits, and from what I've heard he's doing good so it's refreshing to hear."

The BBC understands the church outing does not mark the start of a return to public duties, but is instead a careful first step back into the public eye.

The King was initially greeted by well-wishers when he arrived for the service in a car with Queen Camilla.

A member of the public shouted "Happy Easter!", to which he waved and responded: "And to you," before going into the chapel.

Anne Daley, 65, from Cardiff, held up a Welsh flag when the King arrived and was the first to speak to him when he re-emerged for his walkabout.

She said: "Did you see the smile he gave me? He pointed at my flag."

She added: "He had a lovely smile. He looked well. I think he was happy that we've all come."

The Duke and Duchess of Edinburgh, their son James, Princess Anne and her husband Sir Timothy Laurence, and the Duke and Duchess of York also all attended the service.

The Duke of York and Princess Anne were among other senior royals to attend

The King has not been at public events this year. His cancer was detected while he was undergoing treatment for an enlarged prostate in January. While the type of cancer has not been disclosed, Buckingham Palace has confirmed it is not prostate cancer.

Earlier this week he spoke of his "great sadness" at missing the traditional Maundy Thursday service, which was instead attended by Queen Camilla.

The King attended church in Sandringham in February, shortly after his diagnosis. There, well-wishers gathered as he walked into the church, which is on his private estate in Norfolk, but were not allowed to enter the grounds which are closed to the public until Easter.

Meanwhile, earlier this month, the Princess of Wales revealed in a video announcement that she was undergoing preventative treatment for cancer.

Catherine had abdominal surgery in January, when it was not known there was any cancer, but subsequent tests found it had been present. Her type of cancer has not been revealed.

There is no early return to official duties expected for the princess.

Anne Daley had travelled from Cardiff. "He had a lovely smile," she said. "He looked well. I think he was happy that we've all come."

Queen Camilla has led the line for the royals for the past few months, increasingly carrying out trips on her own that would once have been the responsibility of her husband.

Prince William has kept up projects such as Earthshot and Homewards, but is likely to limit his travels to stay close to home and protect some kind of normal family life.

It is not known how future key dates in the royal calendar, such as Trooping the Colour in June, will be represented by members of the Royal Family, or when the King will return to public engagements.