Mousavian was briefly jailed in Iran in 2007 and charged with espionage. He was later cleared of the charges against him by the judiciary, which declared him innocent "in the spy case and possession of classified documents."
Three years later, the Iranian Intelligence Ministry has again accused him of espionage.
The timing of the accusation against Mousavian has raised questions and led to speculation that it could be linked to the ongoing political infighting within the Iranian establishment. His arrest in 2007 was also seen as part of a factional dispute. Mousavian is said to be close to President Mahmud Ahmadinejad's rival, former President Ali Akbar Hashemi Rafsanjani.
In an August 22 statement, the Intelligence Ministry said Mousavian was "clearly" found guilty of having conducted espionage activities while a member of Iran's nuclear negotiating team under former President Mohammad Khatami. The ministry issued the statement in reaction to comments by the head of Iran's Atomic Energy Organization, Ali Akbar Salehi, who had said a few days earlier that as far as he knew there was no spy in the negotiating team of Iran's reformist government.
The statement said that the Intelligence Ministry "firmly declares that keeping in mind the final verdict issued by Bench 15 of the Revolutionary Court, according to Article 505 of the Islamic Penal Code, Hossein Mousavian has been found guilty for collecting highly classified information under the cover of a system official and delivering them to others (nonqualified people and aliens), and sentenced to two years behind bars and a five-year ban from activities at diplomatic offices, or service at country's other international organs. Therefore, he is clearly found guilty of having conducted espionage activities."
Salehi has reacted by issuing a brief statement in which he said that "the judgment of the qualified authorities" based on legal documents and proof was "more correct "than his own personal understanding and views.
Iranian news websites, including "Khabar Online" have interpreted Salehi's statement as an acceptance of the Intelligence Ministry claim, even though he might have referred to the ruling by the judiciary, which had cleared Mousavian of espionage charges.
Mousavian's lawyer, Houshang Pourbabayi, has reacted to the Intelligence Ministry statement with a statement saying that his client was cleared of espionage charges by three judges who worked on the case.
Pourbabayi writes that "the issue of espionage" was not initially brought against the former diplomat, and it was "put to" his client 10 months after his arrest, in the second Iranian calendar month of 2007.
Pourbabayi has questioned the Intelligence Ministry's statement against Mousavian and asked, "Is this not an insult of the judicial system?"
Mousavian, a former senior nuclear negotiator and former ambassador to Germany, was the head of the Foreign Policy Committee of Iran's Supreme National Security Council. He also worked at the Tehran-based Center for Strategic Research.
Journalist Mehdi Mahdavi Azad, who was arrested in Iran in connection with Mousavian's case, has told RFE/RL's Radio Farda that the "reopening " of Mousavian's case demonstrates that "the real power struggle" in Iran began not after last year's disputed presidential election, but after the 2005 presidential election.
"One of the most important aspects of this struggle is the cutting of ties of the moderate and technocratic forces of the Iranian establishment with the outside world and the diminishing of their power and influence in internal politics," Mahdavi Azad said.
"The statement by the Intelligence Ministry demonstrates that the ministry, which is now under the full control of Ahmadinejad, is following a specific path. Mousavian is one piece of the puzzle."
Mahdavi Azad believes the case against Mousavian is connected to his criticism of Iran's "neoconservatives and ultra-hard-liners". He also said that "the documents" on the basis of which Mousavian was accused of espionage include research papers Mousavian did while working at the Center for Strategic Research and documents related to his time as Iran's top diplomat in Germany.
"Mousavian kept a copy of the documents with the permission of the then-President Hashemi Rafsanjani so that he could defend himself and tell the truth" on a future day of reckoning, Mahdavi Azad added.
Mousavian was the ambassador to Germany during the 1992 assassination of three leading members of the Democratic Party of Kurdistan and an interpreter by Iranian agents in the Mykonos restaurant in Berlin.
Asked whether Mousavian has any documents related to these killings, Mahdavi Azad said: "Mousavian has to answer this question. I know that an important part of the documents are from his time at the embassy in Germany, he kept the documents at his house with the permission of an official above him."
Mousavian said in a June interview with "The Wall Street Journal" that he intended to return to his country at some point. "I don't need asylum from any country, and I would never apply for it," he said.
The recent statement by the Intelligence Ministry suggests that the former Iranian diplomat might not be able to return to Tehran as long as Ahmadinejad is in power.
-- Golnaz Esfandiari