"For all these years my clients have been suffering under this cloud of a multi-million rand defamation claim hovering over them," he said.
"It is not moving forward and it is not being resolved and this is certainly far from ideal. Either he withdraws and tenders wasted costs, or he moves on."
De Klerk is defending the Sunday Sun and Rapport, both part of the Media 24 group.
Zuma spokesperson Mac Maharaj said on Tuesday he did not immediately know how many other cases similar to the Zapiro case Zuma was running against the media, but he was finding out.
After four years Zuma withdrew a claim that was originally R5-million against cartoonist Jonathan "Zapiro" Shapiro and the Sunday Times on Monday.
De Klerk said Zuma had been "in default of the court rules and has been for months".
He alleged that requests, specifically regarding discovery, were "completely ignored".
De Klerk explained that to "discover" was to inform the other side of documents they had relating to the claims.
"A fundamental part of a civil legal action is the disclosure of documents in your possession, so these matters are stuck," said De Klerk.
"He institutes, we defend. We then exchange court documents calling on each other to do things, and he simply ignores all those court documents and notices.
"He is a plaintiff who is non-compliant with the court rules and as such it hampers us."
De Klerk said three separate cases were at issue.
One was a cartoon in the Sunday Sun by Mvuyisi Wilber Mfebe (filed in 2007), and the other a photograph of Leon Schuster and Steve Hofmeyr, captioned "Picnic with Dingane". (filed in 2010).
The third case related to an allegation that Zuma's former financial adviser, Schabir Shaik, arranged a prostitute for him (filed 2008).
De Klerk said he had been informed recently by the counsel handling this particular batch of litigation for Zuma that she had withdrawn. New counsel was yet to be appointed.
He said that in the papers of 2007 and 2008 Zuma described himself as a "politician" and in the third in 2010, he described himself as the President of the Republic.
Beeld reported on Tuesday that other cases still running were:
- R7-million from Primedia relating to a Darren Simpson parody "My name is Zuma";
- R5-million from The Citizen for an article by Paul Kirk alleging Zuma used a prostitute arranged by Shaik;
- R16-million from Rapport for a reader's letter which claimed Zuma was a "rapist who must be punished". That case was settled;
- R16-million from Independent Newspapers relating to Zuma's rape case, two cartoons in The Star where he has his fingers crossed while testifying in court, and a report in The Star titled "ANC gags Zuma".
- R6-million from then Johncom Media for two articles by former Sunday Times columnist David Bullard. Bullard has since apologised.
Yusuf Dockrat, who dealt with the withdrawal of the Zapiro and Sunday Times case on Monday on Zuma's behalf, asked that further queries be made to Maharaj.–Sapa