The Commonwealth's 56 members agreed on Saturday that the "time has come" for talks about the legacy of the "abhorrent" transatlantic slave trade, during a landmark summit declaration that raised the prospect of future reparations.

Gathering in Samoa, leaders from Britain and dozens of former colonies held lengthy and occasionally tense talks over one of the most sensitive aspects of their shared and troubled past.

In a joint statement, Commonwealth leaders noted calls for "reparatory justice" for the "abhorrent" transatlantic slave trade and the "enduring effects" of dispossessing Indigenous people, indentureship and colonialism.