The country's museums needed to decolonise and transform urgently, President Jacob Zuma said in the Northern Cape on Sunday.

"Our museums must be transformed to become centres of heritage and expertise which respect all peoples and cultures," Zuma said in a speech prepared for delivery at the reburial of Klaas and Trooi Pienaar in Kuruman.

The bodies of the couple, who were Khoisan descendants, were dug up and sent to Vienna by Austrian scientist Rudolph Pöch in 1909. They were workers on the farm Pienaarsputs, and died of malaria fever in May and June that year. Their bodies were dug up in October 1909, wrapped in linen and forced into a large barrel, which was filled with salt to preserve them.

Zuma said processes were underway to address the legacy of racial science in museums.

"No museum must have a collection or material that depicts any section of our population as colonial objects, especially indigenous people."

He said the Iziko Museum in Cape Town had already investigated the ethics of its collection.

"The museum decided that all human remains bought from grave robbers or acquired for racial research were unethically collected and needed to be returned."

The arts and culture department would work closely with the museum sector to ensure this happened in line with national policy, said Zuma.