King Charles has described the transatlantic slave trade as a "shameful chapter of history" that filled him with "profound sorrow" as he opened a summit of Commonwealth leaders in the Caribbean.
Speaking at the Commonwealth Heads of Government Meeting (CHOGM) in Antigua and Barbuda, the King said the trade in enslaved persons "still casts a shadow" over the association of nations.
He said: "The transatlantic trade in enslaved persons still casts a shadow over these islands and other members of our Commonwealth. As I have said before, that shameful chapter of history is one that fills my heart with horror and my soul with the most profound personal sorrow."
The King stopped short of issuing a formal apology, despite calls from some quarters for the UK to make one ahead of the summit. He did, however, express contrition and acknowledged that he had personally deepened his understanding of the slave trade's legacy.
"The more I have furthered my own understanding of the issues, through listening, learning and looking, the more committed I have become to finding ways for us to work in modern partnership to address the wrongs of the past with action for the future," he told delegates.
He added: "History is not ours to choose or to change. It is bequeathed to us in complex synthesis by forebears we can never know. Our inheritance includes both their achievements and their failures – the good they did as well as the wrongs."
The King's address also touched on the "brutal conflicts" the world is facing, the "catastrophic reality" of climate change, and rapid technological development.
Prime Minister Andy Burnham, also attending the summit, said he is open to Britain issuing a formal apology for its role in the slave trade but has ruled out financial reparations.
"I've been very clear that we do not support reparations," Burnham said. "But it's not the case that we don't support countries in the Commonwealth around development, and helping them with debt issues that they've got, green finance. That's what we've done under all governments and in my view we should continue to do as part of being a Commonwealth."
Burnham said his government was bringing a new approach to the meeting, aiming to "revitalise the Commonwealth."
CHOGM gathers leaders from 56 states every two years in a different part of the Commonwealth, a voluntary grouping made up primarily of former territories of the British Empire. The official theme of this year's meeting is Accelerating Partnerships and Investment for a Prosperous Commonwealth.
The King and Queen are currently on a tour of the Caribbean, a visit that has reignited debate over the UK's colonial legacy in the region. On his first stop in the Bahamas, the King delivered a speech in which he spoke of the "suffering of the past." In Guyana, he visited the site of a slave rebellion where hundreds of enslaved people were killed.
