Speaking about his father's condition, Hunter said the illness has taken a heavy toll on both Biden and the family.

Hunter Biden has revealed that his father, former United States President Joe Biden, is battling an increasingly difficult stage of cancer, saying the disease has spread to his bones and become "very painful" and "debilitating."

Hunter, the former president's only surviving son, made the emotional remarks in an interview with the BBC published on Saturday, offering one of the most candid updates yet on Biden's health since he disclosed his cancer diagnosis after leaving office.

Speaking about his father's condition, Hunter said the illness has taken a heavy toll on both Biden and the family.

"I wish he would complain more, because it's not good — the cancer has spread," Hunter said.