The Prince of Wales has told Commonwealth leaders the potential of the family of the nations for good cannot be realised until we all “acknowledge the wrongs which have shaped our past”.

Charles described how he was on a personal journey of discovery and was continuing to “deepen my own understanding of slavery’s enduring impact”, in a speech at the opening of a Commonwealth summit in Rwanda.

He recognised the roots of the family of nations “run deep into the most painful period of our history” and acknowledging the wrongs of the past was a “conversation whose time has come”.

But there was no apology from the heir to the throne for the royal family’s involvement in the transportation and selling of people for profit.

For centuries, successive monarchs and other royals participated in the trade, either supporting and facilitating the activity or making money from it.

Charles told the gathering of prime ministers and presidents, who included Boris Johnson, he could not “describe the depths of my personal sorrow at the suffering of so many” during slavery.

The prince is representing the Queen at the Commonwealth Heads of Government Meeting (Chogm), but his visit to the Rwandan capital Kigali has been overshadowed by a row over reported comments he made criticising the Government’s scheme to send asylum seekers to the east African nation.

Prince of Wales shakes hands with Boris JohnsonThe Prince of Wales shakes hands with Prime Minister Boris Johnson as they attend the Commonwealth Heads of Government Meeting opening ceremony at Kigali Convention Centre (Chris Jackson/PA)

A much-anticipated meeting between Charles and Boris Johnson lasted 15 minutes. Before they sat down for talks, Mr Johnson had stepped back from comments he would tell Charles to be open-minded about his Rwanda asylum policy.

The prince told the world leaders the family of nations was “uniquely positioned to achieve such positive change in our world”, adding: “To achieve this potential for good, however, and to unlock the power of our common future, we must also acknowledge the wrongs which have shaped our past.

“Many of those wrongs belong to an earlier age with different – and, in some ways lesser – values. By working together, we are building a new and enduring friendship.”

Charles, who will succeed the Queen as head of the Commonwealth, went on to say: “For while we strive together for peace, prosperity and democracy, I want to acknowledge that the roots of our contemporary association run deep into the most painful period of our history.

ChogmThe Prince of Wales, secretary-general of the Commonwealth of Nations Baroness Scotland, President of Rwanda Paul Kagame and Prime Minister Boris Johnson (Chris Jackson/PA)

“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.

“If we are to forge a common future that benefits all our citizens, we too must find new ways to acknowledge our past. Quite simply, this is a conversation whose time has come.”

Charles also told the world leaders decisions about whether they keep the Queen as head of state or become a republic was an issue for them to make, and a long life had taught him these fundamental changes could be made “calmly and without rancour”.

His comments are likely to be interpreted as acknowledging forces already in motion, as a number of Caribbean nations have already suggested they may ditch the British monarchy and elect their own heads of state.

Prince of Wales visit to RwandaThe Duchess of Cornwall and Carrie Johnson, the wife of Prime Minister Boris Johnson at the opening of the Commonwealth summit (Ian Vogler/Daily Mirror/PA)

“I want to say clearly, as I have said before, that each member’s Constitutional arrangement, as republic or monarchy, is purely a matter for each member country to decide,” the prince said.

Charles and Mr Johnson had met briefly before they joined leaders from the Commonwealth’s 54 member states in the Kigali Conference Centre’s main hall for the opening ceremony.

Delegates included the Sultan of Brunei, the presidents of Botswana, Guyana, Nigeria and Uganda and prime ministers from Canada, Jamaica, St Lucia, Cameroon and Singapore.

The British Prime Minister had warmly greeted the heir to the throne ahead of the Chogm launch, displaying positive body language after he appeared to take a veiled verbal swipe, on Thursday, at the prince and those who have attacked his plans to forcibly remove migrants to Rwanda.

Commonwealth Heads of Government MeetingPrime Minister Boris Johnson, Rwandan president Paul Kagame, secretary-general of the Commonwealth of Nations Baroness Scotland and the Prince of Wales, and Brunei sultan Hassanal Bolkiah (Dan Kitwood/PA)

Charles’s speech to Commonwealth leaders, which also covered the issues of youth opportunity and climate change, was considered an opportunity to “set out his vision” for its future, an aide said.

With 60% of the Commonwealth’s 2.6 billion population under 30, Charles sees ensuring youth opportunity, training and employment as “critical”.

Many member states were “massively impacted” by climate change and so for the prince to bring businesses to Chogm to discuss potential solutions was “critically important”, the aide added.

And Charles realised that in order to achieve that vision the “historic shared past” must be recognised, which meant him making a personal statement about his sorrow.

After the opening ceremony the world leaders went into a closed session to decide whether secretary-general Baroness Scotland should have another term in office.

They re-elected Baroness Scotland, dealing a blow to Mr Johnson, who had wanted her ousted, but their deliberations lasted much longer than expected and meant Charles was unable to host new heads of state at a reception and meet leaders for bilateral talks.

Charles and Camilla ended their visit to Rwanda by hosting a dinner at an exclusive hotel in the capital for the world leaders attending the Commonwealth summit and their partners.

The prince gave a short speech making the delegates laugh when he said he would “report back” to the Queen and how pleased he was seeing them in person and not on a video call with the mute button to “cause confusion”.

He celebrated the cultural heritage of Commonwealth nations from “reggae, calypso, afrobeat” to “curry, jollof rice, maple syrup…and dare I say fish and chips”.

With Birmingham hosting the Commonwealth Games next month Charles ended by saying he was looking forward to visiting the event next month.

He said: “In a world currently riven by conflict and division, these Games, so aptly called ‘the friendly games’, stand as a shining celebration of our unity, our diversity and our pursuit of shared excellence.”