Aides to Iraqi President Jalal Talabani said he would fly to Iran late this week for a meeting with President Mahmoud Ahmadinejad that could also include their Syrian counterpart, Bashar al-Assad.
The United States accuses both Syria and Iran of backing anti-US insurgents and fuelling sectarian violence in Iraq which is threatening to plunge the country into civil war.
State Department deputy spokesman Tom Casey said that while Washington would support any talks that could improve Iraq's stability, it had seen little evidence to suggest Syria and Iran were prepared to change their policy towards their troubled neighbour.
Casey said senior Iraqi and Iranian officials had met in the past, "and we haven't seen much by way of follow-up on it".
"The problem is not what they say, the problem is what they do," he said.
"In our view, the next step would be to have them move beyond those words and actually take some concrete steps," to stabilise Iraq.
Washington specifically wants evidence Iran has stopped providing support to militia in Iraq, some of which are involved in deadly sectarian attacks.
Concerning Damascus, Casey said, Washington is still waiting for action to stop foreign fighters from entering Iraq from Syria.
The talk of a meeting between Talabani and his Iranian and Syrian counterparts comes amid growing pressure on the US administration to review its policy of refusing to talk directly to the two Iraqi neighbours.
British Prime Minister Tony Blair has urged US President George W. Bush to involve both Iran and Syria in efforts to stabilise Iraq, and a congressionally appointed bipartisan panel is expected to recommend such a regional approach when it hands its report to the White House next month.
But Casey said the administration is not yet ready to change course.
"In terms of US relations with Iran and Syria, I think our policy is well-known," he said, referring to remarks last week from both the White House and US Secretary of State Condoleezza Rice that the time was not right for direct talks with either government.

Copyright AFP (Agence France-Presse), 2006