Iran hit back Thursday at US charges that the trial of Washington Post journalist Jason Rezaian on spying charges lacked transparency, insisting its judiciary is independent.
Washington has called for the release of Rezaian, who went on trial behind closed doors on Tuesday, and National Security Council spokeswoman Bernadette Meehan condemned a "complete lack of transparency" in the case.
Rezaian, 39, is accused of "espionage, collaboration with hostile governments, gathering classified information and disseminating propaganda against the Islamic republic", according to his lawyer.
Foreign affairs spokeswoman Marzieh Afkham said it was up to a judge to decide the journalist's fate.
"In any country, questions of justice, judicial process and inquiry have their own procedures," Afkham was quoted as saying on her ministry's website.
"There is no room for premature judgement and speculation."
Rezaian, an Iranian-American, has been held since July last year in a politically sensitive case that has unfolded while Iran and world powers conduct nuclear talks.
Washington says it raises the issue of American nationals detained or missing in Iran on the sidelines of the negotiations.
Tehran does not recognise dual nationality, and says the case is a purely Iranian matter.
Rezaian's wife Yeganeh Salehi, a fellow journalist, also appeared before the court on Tuesday along with a female press photographer, Iran's official IRNA news agency reported.
The two women were detained at the same time as Rezaian but have been granted bail.
According to Mehr news agency, Rezaian was questioned Tuesday over links with an Armenian American journalist, Lara Setrakian, who had allegedly sought information on behalf of US President Barack Obama on the candidates in Iran's June 2013 presidential election.
Obama allegedly also wanted accounts on the political, economic and social situation in the Islamic republic, which brands its arch-foe Washington the "Great Satan".
"As journalists Jason and I spoke often about the Middle East. But at no point did we do anything aside from professional reporting," Setrakian wrote on her Twitter. "I pray for Jason, for his release, and for better days between # Iran and the rest of the world."
State media have given no indication of how long the trial might last.
But it will overlap with the final stretch of negotiations between Iran and the major powers aimed at reaching a comprehensive agreement on Tehran's nuclear programme by a June 30 deadline.