As the DRC awaited new elections, Kabila should step down and allow a transitional authority to lead, he said.
"Now that he has been hosted [by South Africa], that meeting is their private meeting between [President] Jacob Zuma and Mr Joseph Kabila the ex-president of the DRC. The meeting taking place is not in the name of the Congolese people. It is a private meeting," said Mpinda.
Zuma's hospitality to Kabila made him an "accomplice in the atrocities" committed in the vast central African country.
"We are appealing [to] the president of South Africa, if he is indeed a man who stands by the law, who respects the Constitution. His welcoming of Joseph Kabila is saying to the world he is an accomplice in what is happening in the DRC. It is a betrayal. It is a treason case. Jacob Zuma cannot welcome an illegitimate president," said Mpinda.
Zuma was hosting Kabila in Pretoria on Sunday as part of the bi-national commission (BNC). In his opening remarks at the BNC, Zuma congratulated Kabila on the relative stability and progress made in the vast central African nation.
“We gather here at a time when your country is going through a political transition following the December 2016 political agreement. This agreement charted a process that should lead to the next elections,” Zuma said.
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“We congratulate you, Mr President, on the progress achieved thus far and the manner with which you have handled the process. The people of the DRC need to determine and decide their internal political future. The best way to do so is through negotiations and dialogue. The people of the DRC have proven in the past their ability to dialogue.”
Zuma said given the close and strong collaboration between Kinshasa and Pretoria, the South African authorities were pleased to welcome Kabila on his official visit on Sunday.
“We have used the BNC mechanism to identify critical areas of co-operation. The first decade of our BNC was largely consumed by efforts in assisting the DRC in areas of institutional capacity building,” Zuma said.
This included training the DRC national army, police, and diplomats; providing technical electoral support; and conducting the public service census.
“It is clear to us that we have made substantial progress over the years. The DRC of 2017 is different from that of 2004 when we started our collaboration within the context of the BNC. The DRC is now politically stable and the security situation has improved.
“Where there are still challenges, the government of the DRC, with the assistance of the region, continent, and international community, is addressing those. In this regard, we encourage you, Mr President, and your government to continue on this path,” he said.
Zuma urged parties in the DRC to commit to dialogue, even when they differed sharply.
“We wish to reiterate that dialogue and not conflict is the best way to resolve problems. In this regard we wish to assure you of our continued solidarity and support,” he said.