DUBAI: An Iranian court has sentenced Washington Post reporter Jason Rezaian to a prison term, the state news agency said on Sunday, quoting the judiciary spokesman, a case that is a sensitive issue in contentious US-Iranian relations.

The length of the prison term was not specified.

“Serving a jail term is in Jason Rezaian's sentence but I cannot give details,” judiciary spokesman Gholam Hossein Mohseni Ejei told a weekly news conference in Tehran, according to IRNA.

In Washington, US State Department spokesman John Kirby told reporters he was aware of the IRNA report but could not independently confirm it.

It was not immediately clear why Iran has not given details of the ruling against the 39-year-old Rezaian, who Iranian prosecutors accused of espionage.

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The foreign editor of the Washington Post, Douglas Jehl, said in a statement that the newspaper was aware of the reports but that they had no additional information.

“His trial and sentence are a sham, and he should be released immediately,” Jehl said in the statement.

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On October 11, Ejei said Rezaian - the paper's Tehran bureau chief who has both US and Iranian citizenship - had been convicted without elaborating. He said then that Rezaian had 20 days to appeal against the verdict.

The Washington Post said last month that the verdict, issued soon after Iran raised hopes of a thaw in its relations with the West by striking a nuclear deal with world powers including Washington, was “vague and puzzling”.

It said the vagueness of Ejei's remarks showed Rezaian's case was not just about espionage and that the reporter was a bargaining chip in a “larger game”. The Post and his family denounced the espionage charges against Rezaian as absurd.

Influential parliament speaker Ali Larijani hinted in September at the possibility that Rezaian could be freed in exchange for Iranian prisoners in the United States, but officials then played down the possibility of such a swap.

Two other US citizens - Christian pastor Saeed Adedini and Amir Hekmati, a former US Marine Corps sergeant - also are jailed in Iran. Robert Levinson, a private American investigator, disappeared there in 2007.

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Among the charges, Rezaian was accused of “collaborating with hostile governments” and disseminating “propaganda against the establishment”, according to a statement from Rezaian's attorney, the Washington Post reported in April.

In the indictment, Iranian authorities said Rezaian had written to US President Barack Obama and called it an example of contacting a “hostile government”, the Post said.

Rezaian was arrested in July 2014. His brother said on October 13 that Rezaian had heard of his conviction on Iranian state TV and was depressed and angry about being deprived of information about his case.

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