Harry and his wife Meghan have been estranged from the wider royal family since stepping down as working royals in January 2020.
The couple moved to the US and have levelled multiple accusations of racism against members of the royal family.
But CNN reported that the office of the Duke and Duchess of Sussex confirmed Harry had spoken to Charles and that he would travel to the UK in the coming days.
It’s not yet known if Meghan will join him.
It’s understood the public announcement of Charles’ illness – itself a departure from the traditionally tight-lipped royal health protocols – was delayed so the king could personally inform his family.
William, Prince of Wales, has also stepped back from the public spotlight for several days in order to help care for his wife, Princess Catherine, as she recovers from abdominal surgery.
King Charles waves after surgery
Harry’s recent visits to the UK have been brief and short on contact with the other royals.
After Charles’ coronation in May last year, he left the country within hours of the ceremony’s completion.
Charles will begin treatment for his unspecified cancer diagnosis today, Buckingham Palace has announced.
