Deputy President Jacob Zuma has lashed out at National Director of Public Prosecutions Bulelani Ngcuka, accusing him of attempting a "character assassination" of him.

Zuma lodged a formal complaint with Public Protector Lawrence Mushwana yesterday about the way the directorate had conducted its investigation over the past three years of allegations against him.

In a statement, he said his complaint focused on the abuse of power, particularly in the way in which the investigation was carried out.

"I contend that there was no basis for the continuation of the investigation, given that the National Directorate of Public Prosecutions became aware early on that there was no basis for the allegations it claimed initiated the investigation - the alleged attempted solicitation of a bribe by myself from the French company, Thales, as part of corruption in the arms deal."

As early as 2001, the Thales representative concerned had been questioned and told the directorate that no such attempt had been made to him, by Zuma or anyone else in the South African government.

This had been confirmed later in correspondence sent to the directorate by the chairman of Thales who, it had been alleged, had been one of the recipients of the "encrypted fax" soliciting a bribe.

The National Directorate of Public Prosecutions was aware of the impossibility of Zuma's involvement in the arms procurement process as it had been part of the three-agency team that investigated the deal and helped draft the report.

"I've never questioned the right of the National Director of Public Prosecutions to investigate me should he believe there is reason to do so, but I believe the (directorate) had no basis to continue with the investigation, despite the information they received from the French," Zuma said.

"I assert that the National Director of Public Prosecutions conducted the investigation in bad faith, motivated not by the need to earnestly search for the truth, but to cast aspersions on my integrity.

"An example of this is the manner in which detailed confidential information about the investigation was made readily available to certain sections of the media.

"My complaint to the public protector is that in allowing information about the investigation to be released, the national director was not acting in 'good faith' ... What he did was a political act and definitely not a legal act.

"I also raised with the public protector my contention that the conclusion of the investigation against me was extremely prejudicial."

Ngcuka's decision not to prosecute, while saying there was a prima facie case, effectively denied him the opportunity to defend himself, Zuma said.

With acknowledgements to Sapa and the Cape Times.