A United Nations forum on people of African descent opened on Tuesday with calls for extra funding to support its work and progress towards reparations for transatlantic slavery and its legacies in contemporary society.

For over four centuries at least 12.5-million Africans were kidnapped, forcibly transported thousands of kilometres by mainly European ships and merchants and sold into slavery. Those who survived the brutal voyage ended up toiling on plantations in the Americas, mostly in Brazil and the Caribbean, while others profited from their labour.

In a video message at the opening of the third session of the Permanent Forum on People of African Descent (PFPAD) in Geneva, UN Secretary General Antonio Guterres reiterated that racism was based on centuries of enslavement and colonialism. He said reparations should be part of efforts to tackle it.

The idea of paying reparations or making other amends for transatlantic slavery has a long history and remains deeply disputed, but has been gaining momentum worldwide.

"There can be no real discussion about development without a discussion about reparations," said Gaynel Curry, appointed by the Bahamas as a member of the PFPAD, which had its first session in 2022.

The PFPAD suggested last year that a special tribunal should be established to address reparations.

Justin Hansford, a Howard University law professor backed by the US State Department to serve at the forum, called on UN member states to fund the PFPAD so it can continue doing its work. "Back up your words with action," Hansford said.

At the session, which wraps up on Friday, the US Special Representative for Racial Equity and Justice, Desiree Cormier Smith, said the United States had to confront its past of "profound racial injustice".

"Although my country has never fully lived up to the values of freedom and equality for all, we have also never walked away from them - and that's largely thanks to civil society."