All of Iraq's neighbors — including Iran — have agreed to join the United States and Britain at a regional conference in the Iraqi capital on the wartorn country's security crisis, Iraqi officials said Wednesday.

The announcement came as Iran earlier in the day said it was considering whether to participate in the Baghdad-organized gathering.

Ali Larijani, the head of Iran's Supreme National Security Council said that Iranian officials were "reviewing the proposal."

"We support solving problems of Iraq by all means and we will attend the conference if it is expedient," Larijani was quoted by Iranian state TV Web site. "We believe Iraq's security is related to all its neighboring countries, and they have to help settle the situation."

In Iraq, Deputy Foreign Minister Labid Abawi told The Associated Press that no country had rejected the invitation although Russia and France were studying it. "I don't see any sign they will refuse," he said.

Abawi said the United States, Britain, China, Saudi Arabia and Iran had told the government that they will attend and that the date would be set within two days. Iraqi state television said the tentative date for the conference was March 10.

There was no immediate confirmation from Iran.

Washington's willingness to attend the conference, to which Baghdad invited Iran, marked a diplomatic turnabout after months of refusing dialogue with Tehran over calming the situation in Iraq.

U.S. Secretary of State Condoleezza Rice announced a day earlier that the United States would join the meeting, planned for mid-March, and said Washington supported the Iraqi government's invitation to Iran and Syria.

Rice said Tuesday the gathering would be at a sub-ministerial level, to be followed by a full ministerial meeting, possibly in early April.

Larijani suggested that the American presence at the meeting was not a problem for Iran. Asked by reporters if Iran was running a risk by attending the conference alongside the Americans, he replied, "One should not commit suicide because one is afraid of death" — meaning Iran should not hurt itself just to avoid possible negative results.

Iranian hardline President Mahmoud Ahmadinejad said during a visit to Sudan that supporting the "legal government of Iraq, its sovereignty and national unity ... are important elements for solving problems" in that country.

A Tehran state radio commentary said the U.S. should change its Iraq policy if Washington expects the Baghdad conference to produce a "rational conclusion."

Many Iranians feel resentful over the last major diplomatic dialogue with the United States — when officials from both sides met before the 2001 U.S. invasion of Afghanistan to topple the Taliban, whom Tehran also opposed. Iran backed the invasion — only to see Bush name the country part of the "Axis of Evil" later.

The U.S. severed diplomatic relations with Iran in 1979 when Iranian militants occupied the U.S. Embassy in Tehran and held its staff hostage. Washington continues to have diplomatic relations with Syria, including a charge d'affaires at its embassy in Damascus.

The last time the U.S. and Iran had diplomatic contact was in late 2004 during a meeting of 20 nations in the Egyptian resort of Sharm el-Sheik to discuss Iraq's future. Then-U.S. Secretary of State Colin Powell and his Iranian counterpart, Kamal Kharrazi, did not hold formal talks, but Egypt sat the two officials next to one another at a dinner. Powell said the two mostly had "polite dinner conversation," while Kharrazi said the conversation should not be seen as a possible start to better relations.

Syria will be represented at the conference by Ahmed Arnous, an aide to the foreign minister, a Syrian Foreign Ministry official said, speaking on condition of anonymity because the plans had not yet been formally announced.

Syria believes the U.S. participation in the conference was "a partial step .. in the right direction for comprehensive dialogue with Syria on all issues of the Middle East," the state SANA news agency quoted the foreign ministry official.

Along with Iran and Syria, Iraq has invited Bahrain, Egypt, Jordan, Kuwait, Saudi Arabia and Turkey to the discussions. Other Arab countries have yet to confirmed their attendance or the level of delegates they would send.

Iraq's Ahmad Chalabi, an influential Shiite and head of the opposition Iraqi National Congress, said the Baghdad conference was "long overdue" and expressed hope it would help "in building international support" for the Iraqi government.

"The Iraqi people have been waiting for such an international show of support for our struggle against terrorism and to rebuild our country," Chalabi said. "We will never accept Iraq becoming a battleground for other countries, nor will we accept Iraq becoming as base for destabilizing our neighbors."

Iran has said in past months that it is willing to meet with the United States to discuss how to calm the violence in Iraq. But tensions have increased dramatically between the two countries recently.

President George W. Bush has stepped up accusations that Iran is backing anti-U.S. Shiite militants in Iraq, a number of Iranians in Iraq have been seized by U.S. forces and the American military presence in the Gulf has been beefed up.

At the same time, Washington has led a push for stronger sanctions against Iran over the country's nuclear program. The United States accuses Iran of seeking to build nuclear weapons, a claim Tehran denies. The United Nations has demanded Iran suspend uranium enrichment before any negotiations over its nuclear program can be held, a condition Tehran has rejected.