WASHINGTON - The United States left open the possibility on Wednesday that US diplomats could meet one-on-one with Iranian officials on the sidelines of a conference of Iraq's neighbors in Baghdad this weekend.

A woman walks past a mural on a wall at Palestine Square in Tehran, March 4, 2007. [Reuters]

State Department spokesman Sean McCormack said he did not know whether the US diplomats would hold bilateral talks with Iranian officials on Saturday but he did not rule it out.

"We will see what interactions may come about," McCormack told reporters. "I'm not going to point you in the direction of any particular diplomatic interaction, nor am I going to wave you off of any one occurring." he added.

US ambassador to Iraq, Zalmay Khalilzad, and the State Department's Iraq advisor, David Satterfield, will represent the United States at Saturday's meeting, which was called by Iraq to boost support for the government and to curb violence.

Iran's deputy foreign minister is expected to attend the meeting, making it a rare occasion when representatives from Tehran and Washington will come together to discuss Iraq.

The nations are at loggerheads over Iran's nuclear program and the United States accuse Iran of meddling in Iraq and supplying explosives used against US troops. Tehran denies any role in supplying arms.

McCormack said the United States wanted to discuss so-called EFPs at the meeting - the explosively formed projectiles US ed against US military patrols in Iraq and which Washington says are coming over the border from Iran.

"You bet we're going to raise it," said McCormack.

"We're going to take every possible opportunity that we can take to ensure that our troops are protected in-theater. And if that means having a discussion with the Iranian representative in the context of this meeting, yeah, we're going to take that opportunity," he added.

McCormack reiterated the US position that any bilateral meeting with Iran would be restricted to Iraqi security issues and would not touch on Iran's nuclear dossier.

Washington has said it will only negotiate directly with Iran on the nuclear issue once it has abandoned uranium enrichment, which Iran says is for peaceful power purposes and the United States says is aimed at building a bomb.

The United States, which broke off ties with Iran shortly after its 1979 revolution, and other major powers are working on a UN resolution to impose new sanctions on Iran over its nuclear program.

Saturday's meeting, to be attended by Iraq's neighbors, Egypt and the Arab League as well as the permanent members of the UN Security Council, is seen laying the groundwork for a meeting of ministers expected early next month.

US Secretary of State Condoleezza Rice is expected to attend the April meeting but a firm date has not been set.

Washington has in the past been critical of Arab nations for not doing enough to support Iraq's government and McCormack said he hoped countries attending Saturday's meeting would come prepared to discuss what commitment they would make to help.