Alexander Litvinenko's son told an inquiry into his death that he "never truly believed" his father would die and that he was "hit hard" by the news.
Twenty-year-old Anatoly Litvinenko was 12 when his father died. He told the court, "Before this point I never truly believed my father would die. I was young and optimistic and I thought he would recover."
He told the inquiry that his father's death "hit me hard, but at the same time I felt quite numb ... It was very painful to look at him in the state he was in."
"I understood why he disliked Russia. I understood why he liked England and I understood his sentiments towards Chechnya," Anatoly added.
The inquiry into Alexander Litvinenko's death has heard his statement on how he was poisoned. ITV News Correspondent Juliet Bremner reports.
Marina Litvinenko has told the inquiry into her husband's death about the days leading up to his poisoning.
The widow of poisoned spy Alexander Litvinenko told an inquiry into his death that he would not have acquired the materials that killed him.