William, who has spent the past three-and-a-half weeks with Kate and their children during the Easter holidays, returns to public work on Thursday.

The 41-year-old heir to the throne will visit Surplus to Supper, a surplus food redistribution charity, in Sunbury-on-Thames, and then a youth centre in west London which benefits from the organisation's regular deliveries.

Kate, 42, appealed for her family to have time, space and privacy, when she announced in a video message to the nation on March 22 that she had begun chemotherapy.

"This of course came as a huge shock, and William and I have been doing everything we can to process and manage this privately for the sake of our young family. As you can imagine, this has taken time," she said.

"It has taken me time to recover from major surgery in order to start my treatment.

"But, most importantly, it has taken us time to explain everything to George, Charlotte and Louis in a way that is appropriate for them, and to reassure them that I am going to be OK."

The princess's cancer was discovered in post-operative tests following her major abdominal surgery in January.

William was seen taking eldest son Prince George to an Aston Villa football match last week - their first public outing since Kate's announcement.

Kensington Palace said the prince is undertaking this week's engagements to shine a spotlight on the organisation's community and environmental impact.

He will meet volunteers who sort and redistribute food at the charity's hub at Sunbury Cricket Club, and help them load the deliveries into their vans.

William will also lend a hand in the kitchen by joining the team of chefs as they prepare meals.

"Protecting the environment for future generations is one of the Prince of Wales's key priorities," the palace said.

Australian Associated Press