Newsweek magazine on Wednesday repeated a call on Iran to immediately release its correspondent and rejected charges made against him.
Newsweek, in a statement, said Maziar Bahari has been detained in Iran since June 21 without access to a lawyer.
The US news weekly quoted an Iranian state news agency as saying that Bahari "has said he participated in a Western media effort to promote irresponsible reporting in Iran."
"Newsweek strongly disputes that charge, and defends Bahari?s work," the magazine said.
"Maziar Bahari is a veteran journalist whose long career, both in print and in documentary filmmaking, has been accurate, even-handed, and widely respected.
"Newsweek again calls for his immediate release."
Hardline Iranian cleric Ahmad Khatami last week urged the government to "better control" the foreign media, accusing it of fomenting protests after the country's presidential election.
Scores of journalists and reformist politicians have been arrested following President Mahmoud Ahmadinejad's re-election on June 12, which triggered a week of mass protests in Iran and charges of voter fraud.
Besides detaining Canadian-Iranian Bahari, Iran expelled BBC correspondent Jon Leyne and detained a Greek-British journalist, Jason Fowden, who was working for The Washington Times.
