Two Iranians being held by US forces in Iraq were released early Friday, Iranian state television reported without quoting a source.
"Two of the Iranian diplomats who were detained by the American forces were released this morning in the presence of the Iraqi National Security Advisor Mowaffak al-Rubai and the Iranian ambassador to Iraq," Hasan Kazemi Qomi, the report said.
It gave no further details.
Rubai refused to confirm the releases, telling AFP: "I do not wish to comment on this."
The US military press office in Baghdad referred questions about the Iranians to the office of the secretary of defence in Washington, which did not immediately respond to an inquiry.
On Wednesday, military spokesman General William Caldwell said US forces were holding two Iranian nationals detained last week in the Iraqi capital on suspicion of weapons smuggling.
"There was an operation on the morning of December 21 based on intelligence. We conducted a raid on a site in Baghdad," Caldwell told reporters.
Ten people were arrested in the raid and "documents, maps, photographs and videos" were seized which, he said, linked them to "illegal activities". After interrogation it was discovered that two of the 10 were Iranians.
"Debriefing of the detainees and investigation of the seized materials has yielded intelligence linking some of the individuals being detained to weapons shipments to illegal armed groups in Iraq," said a US military statement.
President Jalal Talabani, who invited the two Iranians to Iraq as part of an agreement between the newly forged allies to improve security, was said earlier this week by his office to be "unhappy with the arrests".