Iran's judiciary said on Wednesday the release on bail of two US citizens convicted of espionage was not imminent, state media reported, rejecting President Mahmoud Ahmadinejad's announcement that they will be freed in a couple of days.
Analysts say the contrast between the judiciary's statement and Ahmadinejad's promise highlights a rift between Iran's ruling hardline elites, germinated by Ahmadinejad's disputed 2009 re-election and the protests which followed.
The statement is also an indication of Supreme Leader Ayatollah Ali Khamenei's powerful position in the Islamic state's complex political structure, analysts say.
"Ahmadinejad's announcement could not be made without getting a green light from the leader ... however, the judiciary's move reminded the president of his limitations," said analyst Saeed Monfared.
"Khamenei is a very clever politician ... who avoids empowering others too much ... the two will be freed but not at the time announced by Ahmadinejad."
Ahmadinejad had told US media that the two would be freed "in a couple of days", in what he called a humanitarian gesture shortly ahead of his trip to the United Nations in New York.
But Iran's state television quoted a judiciary statement as saying, "The two Americans are going to stay in prison for a bit longer. Reports of their imminent release are wrong."
Shane Bauer and Josh Fattal were arrested in July 2009 near Iran's border with Iraq, where they say they were hiking in the mountains as tourists, along with a third American, Sarah Shourd. She was allowed home on $500,000 bail in September 2010.
Their lawyer said on Tuesday the pair, who were sentenced last month to eight years jail, would be released on $500,000 bail each. They share a cell in Tehran's Evin prison.
The judiciary said Bauer and Fattal's release on bail was under review and "disseminating information in this regard by others than judiciary officials is not authoritative".
Washington has denied they were spies. US Secretary of State Hillary Clinton said she was encouraged by Ahmadinejad's remarks.
The release of the two Americans could ease the heightening tension between Tehran and Washington, which also says the Islamic state is trying to build nuclear bombs and has imposed sanctions on Iran.
Tehran denies this, saying its nuclear programme is only aimed at generating power and has so far refused to halt its sensitive nuclear work.