Former president Jacob Zuma's "known enemy agent" tweet about former cabinet minister and ANC member Derek Hanekom was "untrue, defamatory and unlawful".

This is according to Durban high court judge Dhaya Pillay, who on Friday ordered Zuma to remove it and publish an apology on Twitter within 24 hours.

Zuma was ordered to pay damages, the quantum of which is to be determined at a future hearing where oral evidence will be led.

Hanekom, the former tourism minister - in Zuma's administration - was suing Zuma for R500,000 in damages after the former president tweeted in July that Hanekom was a “known enemy agent”.

Hanekom said this has caused him “immense harm and damage” because it gave the impression that he was an apartheid spy.

Zuma, in his affidavit, said there were “common cause events” that demonstrated that Hanekom “colluded with opposition parties that sought to remove me as president”.

Judge Pillay also issued an interdict preventing him from ever again stating or implying that Hanekom is an enemy agent or a spy.

She said this will not prevent him from giving honest evidence at the Zondo commission.

Hanekom's lawyers were not present. Attorney Robinson Manzi appeared for Zuma.