King Charles has been urged to go further towards offering reparatory justice for the UK’s role in transatlantic slavery, even as he was praised for reportedly ignoring Boris Johnson’s advice to avoid the issue at all costs. Academics and campaigners called on Charles to adopt specific measures to help build an understanding of the legacy of the enslavement of black people, as well as putting forward suggestions for how the UK could work towards making amends. “He should do far more,” said Brooke Newman, an associate professor of history at Virginia Commonwealth University. “He has the money, obviously, and the connections to create an independent commission to really dig into these connections.” However, she said it was encouraging that Charles appeared to be more willing to listen than some other members of the British establishment. She was joined by other academics and campaigners, who called for a coordinated international effort to reach a consensus on reparations, and warned the king he cannot expect to live out his reign without properly addressing the issue. Their comments came after Guto Harri, an ex-adviser to Johnson, said that the former prime minister warned the then Prince of Wales ahead of the 2022 Commonwealth summit in Rwanda that mentioning slavery in his speech could open the royal family up to reparations claims. Harri wrote in the Daily Mail that Johnson said: “I wouldn’t talk about slavery or you’ll end up being forced to sell the Duchy of Cornwall to pay reparations to those whose ancestors built it.” Sources close to Johnson have questioned the accuracy of Harri’s account. Charles went on to tell Commonwealth leaders: “I cannot describe the depths of my personal sorrow at the suffering of so many as I continue to deepen my own understanding of slavery’s enduring impact.” The king has also subsequently signalled his support for research into the British monarchy’s role. While Newman praised him for that, she suggested the crown go further and pay for an expanded research project, with the money being put into trust to maintain its autonomy. Dr Katie Donington, a senior lecturer in black, African and Caribbean history at the Open University, said such a process would “lead to difficult conversations about slavery and its legacies. That includes material wealth accumulation, but also the legacies of racism which continue to shape inequalities”. They were joined by Robert Beckford, the director of the University of Winchester’s institute for climate and social justice, who said the effort to provide reparation should not be done piecemeal by those willing to acknowledge their roles, but by international consensus. International agreement on a “legal framework for all institutions, groups, individuals and nations” was necessary to provide clarity on what reparations should be paid, he said. Beckford added: “Any prime minister who understands slavery’s history and its ongoing impact on national and international relations would support repairing its damage and healing its significant wounds.” Rishi Sunak recently dismissed calls in the Commons from the Labour MP Bell Ribeiro-Addy to apologise and offer reparations. Beckford expressed hope a Labour government would reverse that. While Labour has previously said calling for reparations is not its policy – and the party declined to comment on Tuesday – one of its MPs, Clive Lewis, said: “I think it’s a testament to the fact that the king, the Prince of Wales at the time, held [Johnson’s] advice in such low esteem that he decided to ignore it … Whatever I think of the institution of the monarchy, it is quite clear that the king is a thoughtful individual.” Nevertheless, the campaigner Esther Stanford-Xosei said the royal family was not doing enough. She called on the king to support the creation of an all-party parliamentary commission to give black people a hearing. She asked: “How can King Charles … think that he will live out his term as monarch without having to make restitution?”