The chair of judges, Peter Florence, emerged after more than five hours with the jury to reveal that the group of five had been unable to pick a single winner from their shortlist of six. Instead, despite being told repeatedly by the prize’s literary director, Gaby Wood, that they were not allowed to split the £50,000 award, they chose two novels: Atwood’s ‘The Testaments’, a follow-up to her dystopian ‘The Handmaid’s Tale’, and Evaristo’s ‘Girl, Woman, Other’, which is told in the voices of 12 different characters, mostly black women, theguardian.com reported.

Evaristo’s win makes her the first black woman to win the Booker since it began in 1969 and the first black British author. At 79, Atwood becomes the prize’s oldest winner. The Canadian author previously won the Booker in 2000 for ‘The Blind Assassin’; she becomes the fourth author to have won the prize twice, after Booker Prize 2019.

The Booker Prize has been split twice before: In 1974, by Nadine Gordimer and Stanley Middleton, and in 1992, by Michael Ondaatje and Barry Unsworth. After 1992, the rules were changed to insist that the prize “may not be divided or withheld”.

After more than three hours of discussions, the jury asked Wood if they could split the prize. They were told no. They went back into discussions for another hour, to come up with the same, unanimous choice. Wood spoke to the chair of trustees, Helena Kennedy, who also insisted on the rules being kept. The jury came back a third time, announcing with what Florence said was “absolute consensus”, that they had decided to ignore the rules.

“We spent a good hour and a half agonizing over how to resolve the issue to the jurors’ satisfaction, and the eventual decision that was taken was a moment of joy for all of us,” said Florence. “We were trying to accommodate the rules that were given to us. How do you equably and fairly resolve something that seems irresolvable? You find a way of changing the game.”

Asked if she supported the decision, Atwood said: “It is an explicit flouting of the rules and they all understood that. It was a rebellious gesture but it was … a generous one.”

She made clear that the rules would not be changed in future – and that this year’s jury was not the first to ask to split the Booker prize.

Florence said “I hope both winning authors will accept this as a mark of respect to two books.”

The chair of judges, who was joined on the judging panel by Liz Calder, Xiaolu Guo, Afua Hirsch and Joanna MacGregor, said that ‘The Testaments’ and ‘Girl, Woman, Other’ were “fully engaged novels, they are both linguistically inventive, they are adventurous in all kinds of ways. They address the world today and give us insights into it and create characters who resonate with us, and will resonate with us for ages”.