Iran has charged a Washington Post reporter who has been detained in the country for nearly five months, the paper said, citing sources familiar with the case.

It said the nature of the charges levelled at Jason Rezaian, the newspaper's bureau chief in Tehran, were not immediately clear as he appeared in court on Saturday.

The source told the newspaper that a translator accompanied Rezaian because he does not read Farsi as he spent about 10 hours in court while his case was reviewed by a judge.

We are dismayed and outraged by reports that Jason Rezaian, The Post's correspondent in Iran, has now been charged with unspecified crimes

- Martin Baron, Washington Post executive editor

Rezaian's family had hired an attorney, but the lawyer was not allowed to visit him, the paper said.

"We are dismayed and outraged by reports that Jason Rezaian, The Post's correspondent in Iran, has now been charged with unspecified crimes," Washington Post Executive Editor Martin Baron said in a statement.

"The Iranian government has never explained why Jason was detained or why he has been held for more than four months without access to a lawyer. Jason is an American citizen who was acting as a fully accredited journalist. If he has indeed been charged, we know that any fair legal proceeding would quickly determine that any allegations against him are baseless," Baron added.

Rezaian, an Iranian-American who holds dual citizenship, was arrested on July 22 along with his wife Yeganeh Salehi, who was freed on bail in October.

Iran does not recognise dual nationality.

The Washington Post said hopes for Rezaian's release rose in late October when a senior Iranian official said possible charges under review by the judiciary might be thrown out.

But last week Rezaian was shown a document signed by the judge overseeing his case and authorising the extension of his detention, the family said.

The document was dated November 18 and said the investigation against Rezaian continued, the newspaper said.

The case of Rezaian, whose family says is suffering multiple health complaints while in detention at Tehran's notorious Evin prison, has been repeatedly raised by the State Department in its talks with Tehran about a deal to curb Iran's nuclear programme, the paper said.

Source: Agencies