South African President Cyril Ramaphosa said attacks on the country's judiciary system and judges by some politicians were worrying.

Ramaphosa said on Monday that allegations that some judges were biased towards certain politicians would result in the erosion of trust in the judiciary.His remarks came after former president Jacob Zuma accused judges of abusing their powers.

Last week Zuma said "it is not our law that I defy, but a few lawless judges who have left their constitutional post for political expediency" after refusing to appear at the state capture inquiry to testify.

Ramaphosa said these unfounded allegations were deeply worrisome. "Of particular concern are recent utterances directed at the judiciary, in which some judges are accused, without any evidence, of pursuing interests other than the cause of justice. Judges have been accused of political agendas and some have even been accused of accepting bribes," he said.

Ramaphosa said these allegations were being taken seriously and said institutions to deal with such were in place.

"There are clear processes established in law to deal with allegations of misconduct against members of the judiciary," he added.