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The United States ambassador in Baghdad said he and his Iranian counterpart agreed broadly on policy toward Iraq during four-hour groundbreaking talks on Monday, but insisted that Iran end its support for militants.

During a meeting that U.S. Ambassador Ryan Crocker described as businesslike, the American said Iran proposed setting up a "trilateral security mechanism" that would include the U.S., Iraq and Iran. Crocker said the proposal would need study in Washington.

"We will consider that when we receive it," Crocker told reporters in the U.S.-controlled Green Zone. "The purpose this meeting was not to arrange other meetings," he said.

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The U.S. envoy also said he told the Iranians their country needed to stop arming, funding and training the militants.

"This is about actions not just principles, and I laid out to the Iranians direct, specific concerns about their behavior in Iraq and their support for militias that are fighting Iraqi and coalition forces," Crocker told a Green Zone news conference.

Crocker also disclosed to that the Iraqis said they would be proposing a second session.

Iranian Ambassador Hassan Kazemi Qomidid not raise the subject of seven Iranians now in American custody in Iran, crocker said.

"The focus of our discussions were Iraq and Iraq only," Crocker said.

In the course of the meeting, Ali al-Dabagh, a government spokesman, told reporters that the session was proceeding cordially.

"There are good intentions and understanding and commitment between the two countries," al-Dabagh, told reporters.

The talks were held at Iraqi Prime Minister Nouri al-Maliki's Green Zone office.

Just before 10:30 a.m., al-Maliki greeted the two ambassadors, who shook hands, and led them into a conference room, where the ambassadors sat across the table from each other. Al-Maliki then made a brief statement before leaving.

He told both sides that Iraqis wanted a stable country free of foreign forces and regional interference. The country should not be turned into a base for terrorist groups, he said. He also said that the U.S.-led forces in Iraq were only here to help build up the army and police and the country would not be used as a launching ground for a U.S. attack on a neighbor, a clear reference to Iran.

"We are sure that securing progress in this meeting would, without doubt, enhance the bridges of trust between the two countries and create a positive atmosphere" that would help them deal with other issues, he said.

Speaking in Tehran, Iranian Foreign Minister Manouchehr Mottaki said Monday the talks could lead to future meetings, but only if Washington admits its Middle East policy has not been successful.

"We are hopeful that Washington's realistic approach to the current issues of Iraq by confessing its failed policy in Iraq and the region and by showing a determination to changing the policy guarantees success of the talks and possible further talks," Mottaki said.

Monday's talks, as predicted, had a pinpoint focus: What Washington and Tehran -- separately or together -- could do to contain the sectarian conflagration in Iraq.

"The American side has accusations against Iran and the Iranian side has some remarks on the presence of the American forces on Iraqi lands, which they see as a threat to their government," al-Dabagh said.

But much more encumbers the narrow agenda -- primarily Iran's nuclear program and more than a quarter-century of diplomatic estrangement after the 1979 Islamic revolution in Iran.

Further, the Iranian Shiite theocracy fears the Bush administration harbors plans for regime change in Tehran and could act on those desires as it did against Saddam Hussein in Iraq.

Washington and its Sunni Arab allies, on their side, are deeply unnerved by growing Iranian influence in the Middle East and the spread of increasingly radical Islam.

Compounding all that is Iran's open hostility to Israel.

Those issues, combined, are the nut of the larger problem and what make this opening of the U.S.-Iranian minuet both so important and so interesting.

Would this first meeting spawn a second session as the Iranians apparently plan to proposed.

If Washington were to accept, would a future dialogue involve higher-level officials -- perhaps U.S. Secretary of State Condoleezza Rice and Mottaki.

Many other issues could cloud the talks. There were U.S. Navy exercises in the Persian Gulf last week and tough talk from U.S. President George W. Bush about new U.N. penalties against Tehran over its nuclear program. The United States says Tehran is trying to build a bomb. Iran says it needs nuclear technology for energy production.

Further complicating the talks, Iran said Saturday it had uncovered spy rings organized by the United States and its Western allies.

Iran accuses the U.S. of improperly seizing five Iranians in Iraq this spring. The U.S. military is holding the five. Iran says they are diplomats; Washington contends they are intelligence agents.

The U.S. also has complained about the detention or arrest of several Iranian-Americans in Iran in recent weeks. State Department spokesman Tom Casey said that issue is not on the U.S. agenda for Monday.

Regardless, the Baghdad talks were the first of their kind and a small sign that Washington thinks rapprochement is possible after nearly three decades of animosity. Iran, angry over the blunt show of U.S. military power off its coast, almost refused to come.

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