The King has told world leaders the past cannot be changed, but nations can “commit” to “right inequalities that endure”, as momentum grew for a debate about slavery reparations.

Charles used his first major speech as head of the “family of nations” to highlight how the “most painful aspects of our past continue to resonate” with the people of the Commonwealth.

But he urged the institution, celebrating its 75th anniversary, to adopt “the language of community and respect, and reject the language of division” when considering “deeply concerning challenges”.

Sir Keir Starmer has joined presidents and prime ministers at the Commonwealth Heads of Government Meeting (Chogm) being hosted by Samoa, and insisted reparations are not on the table for the summit.

World leaders will elect the new Commonwealth secretary-general to replace Baroness Scotland during their meeting, and all three candidates vying for the job have called for reparations to countries that were affected by slavery and colonialism.

Strength of feeling among some member states appears to be growing for Britain to contribute financially for its historical role in the slave trade, and the UK has conceded the issue of reparations could be included in a document due to be signed off at Chogm.

Charles opened the summit with his speech telling the global leaders: “As we look around the world and consider its many deeply concerning challenges, let us choose within our Commonwealth family the language of community and respect, and reject the language of division.

“None of us can change the past. But we can commit, with all our hearts, to learning its lessons and to finding creative ways to right inequalities that endure.”

The King and Queen meet Sir Keir Starmer
Sir Keir Starmer will also take part in the summit (Toby Melville/PA)

The King spoke to a number of leaders via telephone before the summit began, and from the comments in his speech appears not to be taking sides on the major issues but sounding a conciliatory note, calling for the Commonwealth family to work through its problems together.

Charles highlighted how the fundamental strength of the Commonwealth is its diversity: “Together, we represent a third of humanity, with all the splendidly diverse complexity that this entails. And yet we know and understand each other, such that we can discuss the most challenging issues with openness and respect.

“At a time of heightened global tensions, of horrifying conflict and challenges of the greatest magnitude, it seems to me that these connections between us are more precious than ever. Together we are wiser, stronger and more able to respond to the demands of our time.

Charles at the Chogm meeting
Charles told world leaders that the past cannot be changed, but hailed the Commonwealth’s strength and unity (AP)

“That said, our cohesion requires that we acknowledge where we have come from. I understand, from listening to people across the Commonwealth, how the most painful aspects of our past continue to resonate.”

Downing Street had sight of the speech before Charles delivered it and when the King met the Prime Minister, Sir Keir praised it, saying: “Your Majesty, great speech.”

When Charles replied: “Well, it was very long,” the politician reiterated: “It was great.”

During his speech, the King looked back to a period when not all members of the British Empire were treated the same, saying: “Few of our forebears could have imagined the Commonwealth of today.

“Our free association of proudly independent nations, alive with opportunity, stands in proud defiance of the discrimination of the past.”

Towards the end of his address the King, who is being treated for cancer, told the summit: “For my part, I can assure you today that for however many years God grants me, I will join you and the people of the Commonwealth on every step of this journey.”