A Belgian court has ruled that a former diplomat can stand trial in connection with the killing in 1961 of Patrice Lumumba, Congo's first prime minister.

Etienne Davignon, now 93, is accused of involvement in the unlawful detention and transfer of Lumumba and of his degrading treatment. Davignon was a trainee diplomat at the time and went on to become a vice-president of the European Commission.

He is the only surviving member of the 10 Belgians accused in a criminal case brought by Lumumba's family in 2011.

The independence hero was executed by a firing squad and his body was dissolved in acid.

Belgium, the former colonial power, has recognised its responsibility and apologised both to Lumumba's relatives and the Democratic Republic of Congo - as the country is now known.

The leader's grandson Mehdi Lumumba welcomed the decision by a Brussels court that Davignon could stand trial. "We are all relieved," he told the AFP news agency. "Belgium is finally confronting its history." The ruling is subject to appeal.

Lumumba was appointed prime minister after Congo gained independence in June 1960. He was one of the most prominent voices in Africa's anti-colonial movement.

Although Belgium had relinquished power, it viewed Lumumba as a threat to its continued economic and political influence in the country.

In a famous speech on independence day, in front of Belgian dignitaries including King Baudouin, Lumumba, aged 34, castigated Belgium saying that the Congolese had been held in "humiliating slavery".

He was ousted in a coup in September 1960 and captured two months later. In January 1961, with the tacit backing of Belgium, he was shot along with two associates.

Although Lumumba denied being a communist, other Western powers were also suspicious of him, fearing that he was sympathetic to the USSR during the Cold War.

A 1975 US Senate inquiry found that the CIA had plotted to assassinate him, though the plan was not carried out and Lumumba was killed by Belgian-backed Congolese forces.