Dame Esther Rantzen has paid tribute to Sir John Hurt’s big-hearted charitable nature, saying she thinks it stemmed from a problem in his childhood.

Childline founder and president Dame Esther said the late actor, who was a fundraiser for the children’s charity, had achieved an “extraordinary career”.

She said: “There was something in his own past which made him connect with vulnerable children – I believe it happened when he was in school.

“From then on he never turned us down, he spoke at events for us, telling stories of some of the children we had helped, and took part in carol services for us.”

“He will be a great loss to the children in this country,” she added.

Meanwhile, co-star Natalie Portman, who he appears alongside in the Jackie Kennedy biopic Jackie, praised his talents.

She said she was “so extremely sad” to hear of Sir John’s death and added: “I was lucky enough to make two films with him – both of which were taken to the next level because of his performances.

“He was the most talented actor, and also a deeply good and funny and poetic and smart and warm human being.

“I send my love to his family at this terrible time, and join his fans in watching his films that we are lucky enough to have forever.”