The Washington Post journalist Jason Rezaian, right, and his Iranian wife Yeganeh Salehi, who works for the UAE newspaper National, during a foreign ministry spokeswoman weekly press conference in Tehran, Iran, 10 September 2013. (Stringer/EPA)

The detention of Washington Post reporter Jason Rezaian and two other journalists in Iran is an internal matter in which the United States has no say, a senior Iranian official has told a prominent conservative newspaper.

The remarks by Deputy Foreign Minister Hassan Ghashghavi, published Wednesday, are only the second government comment on the case since Rezaian, his wife and two others were detained July 22. One was released, and the others have not been heard from since.

Iran has not announced any charges, and it is not clear where the three are being held.

The detentions concern Iranian citizens and are a matter for Iran to adjudicate, Ghashghavi said, speaking in Farsi. He was quoted by the hard-line daily Vatan-e-Emrooz, and his remarks were translated and reported by Agence France-Presse and other news media in Tehran.

Rezaian, 38, and a photojournalist arrested at the same time are dual Iranian and American citizens. Rezaian’s wife, Iranian journalist Yeganeh Salehi, is also being held. At his family’s request, The Post is not publishing the name of the photojournalist.

“We do not accept dual nationalities. If a person enters Iran with an Iranian passport, that person is considered an Iranian citizen,” Ghashghavi said, according to AFP. “We do not allow other countries to demand consular rights on behalf of Iranians.”

The State Department has sought access to the Iranian Americans in detention through Switzerland, which acts as an intermediary because the United States and Iran have no diplomatic relations. Visits by Swiss Embassy personnel, called consular visits, are routinely denied when detainees are dual nationals.

The United States has called for the immediate release of Rezaian and the others.

“So far, we have not received a letter requesting freedom for these journalists,” Ghashgavi was quoted as saying. “But as it is about journalists, the matter could be followed up through foreign diplomatic channels.”

That may be a reference to Switzerland, although it was not clear what he meant.

State Department spokeswoman Jen Psaki said Tuesday that she had no update to report on the Swiss request, and it is not clear whether Iran has denied the request outright or declined to respond.

Washington Post Executive Editor Martin Baron has written to the press counselor at Iran’s mission to the United Nations to ask that Rezaian and the others be released.

“Sadly, inexplicably, we continue to hear nothing from Iran about Jason, his wife Yeganeh, and other detainees,” Baron said in a statement Wednesday. “We do not know where he is, we do not know why he is being held, and we know nothing about his health — which is a particular concern to us and his family. Those familiar with Jason’s work have remarked on his genuine desire to offer insight into Iran’s culture and people, and we can imagine no good reason for him to be held. We dearly hope that Jason, his wife, and others will regain their freedom soon.”

The only previous Iranian government comment on the case, three days after the arrests, suggested espionage or acts of subterfuge, but the authorities have made no specific allegations.

A columnist for Vatan-e-Emrooz has claimed that Rezaian was involved in the creation and release of a YouTube video of unveiled Iranian women dancing to the Pharrell Williams hit song “Happy.” The video caused an uproar in Iran this spring.

Rezaian wrote about the video in May.