Congo's government failed to organise elections by the end of June as laid out in a 2003 peace agreement to end a devastating five-year war. Security forces last week clashed with protesters angry at the delay, killing at least one person.
Kabila told Belgian daily Le Soir in an interview the protests were part of a plot to destabilise the country and create confusion and disorder.
"I'm going to be direct: I think the aim of the organisers of these demonstrations was to overturn the institutions of the transition (government) in order to make it impossible to organise elections," he told the paper.
"Chaos would serve some politicians well," he said, adding that he was open to dialogue but not to delay the electoral process.
Kabila said investments will only reach Congo if it is secure and politically stable.
"And in the long term, these two issues are linked to organising elections. Legitimacy has to come from the polls," Kabila said. "Elections, and nothing but elections."
Congo's conflict killed around 4 million people, mainly from war-related hunger and disease, in a nation roughly the size of western Europe.
Despite the 2003 peace deal, the resource-rich country has seen little economic progress and the government has failed to impose its authority over vast areas of the east, where armed gangs still pillage and kill with impunity.
- Reuters - Thomson Reuters Foundation
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