South African President Cyril Ramaphosa warns against attempts to erode stability

President Cyril Ramaphosa on Saturday said any attempts to undermine South Africa's democracy would fail, a week after a fire devastated the National Assembly building and months after deadly riots rocked the country.

In an address during birthday celebrations of his ruling ANC in the northern city of Polokwane, Ramaphosa said the country had in recent years experienced actions "that have the effects of subverting our constitutional democracy".

"We are in the process of reforming our law enforcement agencies, our security sector, so that it's better positioned to defend the gains of our democracy," he told around 2,000 African National Congress supporters gathered at a stadium.

Ramaphosa cited a devastating fire starting last Sunday that tore through the parliament building in Cape Town and the deadly July riots sparked by the jailing of his predecessor Jacob Zuma among examples aimed at undermining the country's security and stability.

"The entire country has been shocked, outraged and saddened by the destruction because the institution of parliament is a repository of our democracy and symbol of democratic stability of our people," he said.

Days after the fire, a man was arrested after he was found hammering down windows of the country's Constitutional Court in Johannesburg.

On the eve of the ANC's 110th birthday celebrations on Friday night, Ramaphosa's dinner speech to a gathering of businesspeople and senior party officials was abruptly brought to an end by an unexplained power outage.

Ramaphosa tried to downplay the blackout, which local media is speculating was a security risk and which Police Minister Bheki Cele said is under investigation.

The president also cited "blatant" state corruption and criminality, outlined in a partial report handed to him earlier this week by judicial investigators, as other acts undermining South Africa's democracy.

"These desperate efforts will fail," Ramaphosa vowed.

• Africa