U.S. troops detained two Iranians who were in Iraq at the invitation of Iraqi President Jalal Talabani, a presidential spokesman said Monday.

The detentions come as the Iranian president, Mahmoud Ahmadinejad, tries to expand Iran's role in Iraq as a counter to U.S. influence in the Gulf region, and as the Bush administration has resisted pressure for a diplomatic push that would involve all of Iraq's neighbors — including Iran and Syria.

The New York Times reported Monday that U.S. forces were holding four Iranians, including some seized at the compound of Abdul-Aziz al-Hakim, the leader of the largest Shiite bloc in Iraq's parliament, who met with President Bush earlier this month at the White House. The Times said U.S. forces also stopped an Iranian embassy car last week and detained two Iranian diplomats, their Iranian guards and an Iraqi driver. The diplomats were later released by Iraq, it said.

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"Two Iranians who are in Iraq at the invitation of the president have been apprehended by the Americans," said Hiwa Osman, Talabani's media adviser. "The president is unhappy about it."

Osman had no further details. The U.S. military said it had no comment.

A Pentagon official, speaking on condition of anonymity because of the delicacy of the situation, confirmed that Iranians had been among those detained during recent operations against people planning attacks against coalition forces and Iraqis.

The United States has accused Iran of supplying money, weapons components and training to Shiite militia in Iraq, as well as technology for roadside bombs, the biggest killer of American forces in Iraq. Iran says it only has political and religious links with Iraqi Shiites.

Late last month, Talabani visited Iran for two days of talks with government officials to seek their support in quelling the raging sectarian violence in Iraq. Iran, a Shiite Muslim country, has considerable influence among Iraq's Shiite majority — elements of which have been blamed for the bulk of the recent attacks.

Talabani is a member of Iraq's Kurdish minority, but he had close ties with Iranian officials before Saddam Hussein was overthrown by the U.S.-led invasion in 2003.

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