President Thabo Mbeki suspended prosecutions head Vusi Pikoli because he posed a "threat to national security", his lawyers said on Thursday.

Pikoli's legal team released the letter Mbeki wrote to Pikoli to inform him of his suspension, as public hearings into whether Pikoli was fit to hold office continued on Thursday.

"I have evaluated the information at my disposal and have reached the conclusion that you, in your capacity as National Director of Public Prosecutions have failed to appreciate the nature and extent of the threat posed by members of organised crime syndicates to our national security," Mbeki wrote.

"Such a lack of appreciation in itself amounts to a threat to our national security," he said in the letter which Pikoli's lawyers provided to Sapa.

Mbeki also warned Pikoli that plea bargaining and immunity arrangements could not be done "at the expense of our national security".

"Organised crime poses a serious threat to our national security. While I accept that the Prosecuting Authority has the discretion to enter into plea bargains and or immunity arrangements, the public must always be considered.

"Accordingly, in determining what is in the public interest, before exercising such discretion, the Prosecuting Authority must necessarily have regard to the totality of information available to the state."

Only in the third-last paragraph does Mbeki refer to the breakdown in the relationship between Justice Minister Brigitte Mabandla and his office "due to several incidents".

"Accordingly, this letter serves to inform you that I ... have decided to suspend you from office with immediate effect. You will continue to receive your full benefits during the period of suspension," Mbeki wrote.

The Scorpions late last year made a deal with drug kingpin Glen Agliotti - a close friend of suspended police chief Jackie Selebi. He pleaded guilty to drug dealing in a special plea and sentencing agreement, and in return he agreed to testify against syndicates importing and exporting drugs.

The Ginwala Commission has heard detailed evidence on the issue of plea bargaining since its start on Wednesday.

(pick up as required).

Sapa