Britain's Princess of Wales has issued a personal message for the first time since announcing that she is undergoing cancer treatment in March.

Catherine, who is married to Prince William, said in a statement on Friday that she is making "good progress."

She also revealed that she will attend a parade on Saturday to celebrate the birthday of King Charles.

It will be her first public appearance since December.

The 42-year-old royal underwent abdominal surgery in January. She was later found to have cancer and suspended her official duties to focus on treatment.