Belgium's monarch expressed his "deepest regrets" on Tuesday for colonial abuses in the DRC, in an unprecedented gesture for his country that Kinshasa swiftly hailed as "balm" for the Congolese.
King Philippe made his remarks in a letter to Democratic Republic of Congo President Felix Tshisekedi on the 60th anniversary of Congo's independence on June 30, 1960.
The death of African American George Floyd last month as he was being arrested by police in the US city of Minneapolis has also stoked fresh debate in Belgium over its colonial record.
Belgium's colonisation of the vast mineral-rich country was one of the harshest regimes imposed by European powers that ruled most of Africa in the late 19th and 20th centuries.
The scars remain, with two-thirds of the population living below the poverty line and the country riven by conflict and instability.
"I want to express my deepest regrets for these wounds of the past whose pain is reawakened today by the discrimination still present in our societies," Philippe said.
Historians say that millions of Africans from areas in what is now the DRC were killed, mutilated or died of disease as they worked on rubber plantations belonging to Leopold II, king from 1865-1909.
King Philippe, without mentioning Leopold by name, said that during this period "acts of violence and cruelty were committed which weigh on our collective memory".
"The colonial period which followed (1908-60) also caused suffering and humiliation," he said.
On the day Congo broke away from Belgian colonial rule, the country's prime minister and independence icon, Patrice Lumumba, delivered a scathing speech about the racist maltreatment.
"We experienced the slurs, the insults, the beatings that we had to undergo morning, noon and evening, because we were negroes," he proclaimed.
DRC Foreign Minister Marie Ntumba Nzeza, in statement to AFP, said the king's letter was "balm to the heart of the Congolese people. This is a step forward that will boost friendly relations between our nations".
King Philippe said he would combat all forms of racism and wanted to encourage reflection on the issue begun by the Belgian parliament.
Several statues of Leopold, who ruled between 1865 and 1909, have been daubed with paint or torn down by protesters in Belgium in recent weeks, and a petition has been launched for their removal. - AFP