“Some other issues have been brought up about the equipment they had with them (at the time of their arrest), and because of this another case has been opened and is being followed up,” Jamal Karimi-Rad told reporters.
“They are not supposed to be released so soon,” he added.
Frenchman Stephane Lherbier, 32, and German national Donald Klein, 52, were sentenced to 18 months in jail in January by a court in Bandar Abbas in southern Iran where they were initially imprisoned.
An appeals court in March upheld their sentence and they were transferred to Tehran’s Evin prison.
Lherbier had set up a fishing business in the United Arab Emirates, and on November 29, 2005, had set out with his German client. The two were arrested near the island of Abu Mussa, which is Iranian territory but is claimed by the United Arab Emirates.
The two men said they had mistakenly used Emirati maps that did not show the current maritime boundaries.
Karimi-Rad’s comment about their equipment appears to be over a GPS global positioning device.
During their first trial a defence lawyer said the court had dropped any charge of spying.
And in April, following an appeal by the wife of the Frenchman, the head of the Iranian judiciary Ayatollah Mahmoud Hashemi Shahrudi reportedly issued a special order for a new investigation into the case.
In June, Germany’s Interior Minister Wolfgang Schauble refused to meet his visiting Iranian counterpart Mostafa Pour-Mohammadi because of Iran’s refusal to free the prisoner.
On June 28, French foreign ministry spokesman Jean-Baptiste Mattei said Paris was hoping for an act of “clemency” by the Iranians.
Germany and France are both at the centre of international efforts to coax or force Iran into suspending its sensitive nuclear energy programme, which despite Iranian denials is seen in the West as a cover for possible weapons development.
The two detainees are not the only foreign nationals recently held in Iran.
In May, an Iranian court jailed two Swedes for three years for photographing military installations, naval facilities and telecommunication posts on the island of Qeshm — not far from where Lherbier and Klein were arrested.
Karimi-Rad made no mention of the two Swedes.
