(CNN) The King of Belgium has sent his "deepest regrets" to the President of the Democratic Republic of Congo (DRC) for the "suffering and humiliation" his nation inflicted while it colonized the region -- but stopped short of apologizing for his ancestor Leopold II's atrocities.
On the 60th anniversary of the DRC's independence, King Philippe of Belgium wrote a letter to President Félix Antoine Tshisekedi Tshilombo in which he admitted that "to further strengthen our ties and develop an even more fruitful friendship, we must be able to talk about our long common history in all truth and serenity."
The acknowledgment is a watershed moment in Belgium's post-colonial history, and a rare admission of imperialist sins from the royal family -- even if Philippe did not go as far as formally apologizing.
"Our history is made of common achievements but has also experienced painful episodes. During the period of the Congo Free State, acts of violence and cruelty were committed, which still weigh on our collective memory," the King wrote.
Philippe is a distant nephew of Leopold II, who owned what was then called Congo Free State between 1885 and 1908 and ruled its people brutally, exploiting their labor and committing atrocities against them. Historians estimate that under Leopold's misrule, as many as 10 million people died.
"The colonial period which followed also caused suffering and humiliation," the letter adds, referring to the subsequent 52 years of rule by the Belgian state until Congo's independence and the formation of the DRC.
"I would like to express my deepest regrets for these wounds of the past, the pain of which is now revived by the discrimination still too present in our societies," he added.
"It wasn't (previously) announced, so it was surprising that it was today. But I think it's a very good sign," Els Van Hoof, a Belgian MP who leads the chamber of representative's foreign affairs committee, told CNN of the monarch's letter. "It's the beginning of a process -- and it's a process in parliament but also in society."
The letter also marks a significant victory for the anti-racism protesters who have been demanding Belgium address its colonial past and remove public monuments to Leopold II.
One unlikely leader of the demonstrations is a 14-year-old called Noah, whose petition to take down Brussels' monuments has been signed tens of thousands of times. He told CNN on Tuesday that the letter was "a good first step."
"I want concrete acts," he added, calling for wider education of Belgium's colonial past. "There are still people who don't know this history... there are lots of people who want to deny or don't understand what happened. It is very much about finding the truth. It is never too late. Perhaps it could have happened 60 years ago, but if it happens now it is good."
A reassessment of Belgium's colonial legacy has taken place in the wake of the global Black Lives Matter protests, with several statues depicting the former leader have been taken down in the country. Earlier this month, Belgium's parliament approved an inquiry into its colonial history, led by lawmaker Van Hoof.
"I welcome the process of reflection that our parliament has started, so that we may finally make peace with our memories," the King wrote. But he did not take the opportunity to apologize to the DRC for the acts committed by Leopold II or by Belgian governments until 1960.
"Is it only the King that has to apologize or does it have to go further than that? I think it has to go further than that," Van Hoof told CNN on Tuesday. "That's the work of the committee -- in the end, we will see who has to apologize."
The lawmaker did not commit to recommending all statues of Leopold II are taken down, as many activists have demanded. "You have to contextualize and explain, and make it part of a process," she said.
But Van Hoof said that the voices of Black Lives Matter activists would be heard when the inquiry fields public input towards the end of the year. She added that Philippe's statement was "a good first step so that we finally can deal with our past, because it hasn't happened before."
The DRC was finally established on June 30 1960, a date marked by a historic speech from independence leader Patrice Lumumba in which he described eight decades of subjugation that were "filled with tears, fire and blood."
A Leopold II statue in Antwerp was removed after Black Lives Matter protests swept around the globe earlier this month, while another opposite Brussels' Royal Palace has been repeatedly covered in anti-racist graffiti.
"We want an apology, a real one. Not one that asks us to read between the lines," Joelle Sambi Nzeba, a Belgian Black Lives Matter activist, told CNN on Tuesday.
Sambi Nzeba said that all such statues should be taken down and replaced by monuments recognizing Congolese people who had been killed. "We want to discuss who benefits from colonization," she added.
With no immediate offer of visas, very few Congolese people came to Belgium until recently -- so while the country became home to people from a number of European nations, colonial sentiments towards African cultures have never been fully shaken off in the country.
That prevailing attitude has led to a number of high-profile incidents of blackface in the country, including by leading politicians, and a general lack of education around Belgium's imperialist past. Last year, a group of UN human rights experts visited several cities in Belgium and found "clear evidence that racial discrimination is endemic in institutions in Belgium."
But Berry College historian Matthew Stanard, who specializes in colonial memory in Belgium, told CNN that a direct acknowledgment of past offences from the royal family is a new concession.
"There's a whole generation of younger people in Belgium who have nothing to do with colonialism, and who are willing to question the colonial past," Stanard said. "Views of (Leopold II) are deeply polarized -- the number of people who have come out speaking against him has definitely grown."
Correction: This story has been updated to correct the spelling of Joelle Sambi Nzeba's name.