Attorney General Menachem Mazuz recently rejected a request by Nahum Manbar for an early release from prison. Manbar was convicted in 1997 of selling equipment and know-how to Iran for the manufacture of chemical weapons.

Manbar, who has already served two-thirds of his 16-year sentence, appealed to Mazuz after the Tel Aviv District Court rejected the petition for parole that he had filed in March. In his appeal, he requested that the state rescind its objection to his early release.

The request was an unusual one, since the normal process is for the prisoner to ask the Parole Board for an early release and then appeal its decision if necessary to a district court. Prisoners rarely appeal directly to the attorney general.

A spokesman for Mazuz told Haaretz that in view of the serious security offenses of which Manbar was convicted, and particularly their connection to Iran, given the threat that Tehran currently poses to Israel, an early release of the prisoner would undermine both the public's confidence in the legal establishment and the state's deterrent capacity against others who might consider harming national security.

Manbar's request for parole was accompanied by letters of support from former security officials and an up-to-date professional assessment stating that his release would not undermine national security.

Manbar, a businessman, was convicted of aiding an enemy state, attempting to aid an enemy state and passing knowledge to an enemy state with the intention of harming national security. One of the main charges against him was that he gave Iran know-how, including a list of the necessary equipment, that would help it set up factories for the production of two chemical warfare agents, mustard gas and nerve gas. He received millions of dollars in exchange.

In his response to Manbar's request, Mazuz wrote that there is no reason for the state to alter its stance on his case and support his parole. He based his decision on the Tel Aviv District Court's ruling, which rejected Manbar's request for parole on the grounds that the nature and gravity of his crimes made it impossible to grant him an early release.

Manbar appealed to the district court after the Parole Board refused to cut his prison term by one third. The Parole Board's decision was based in part on the assessment that Manbar continues to constitute a threat to national security.