The Pentagon says Iran has sent a small number of operatives to help Iraq, but has no "major units" there.

Iran has sent "small numbers" of operatives into Iraq to bolster the Shiite-led government in Baghdad, but there is no sign of a large deployment of army units, the Pentagon said Friday, according to AFP.

The comments by Pentagon spokesman John Kirby marked Washington's first public confirmation that Iranian operatives had crossed into Iraq, where the Baghdad government is struggling to counter the swift advance of Sunni extremists.

"There are some Iranian revolutionary operatives in Iraq but I've seen no indication of ground forces or major units," Kirby told a news conference, apparently referring to Tehran's Quds force, the covert arm of the Revolutionary Guard Corps.

"Their interference in Iraq is nothing new," Kirby said, referring to Washington accusing Tehran of sending forces to Iraq when U.S. troops were in the country, between 2003 and 2011.

Reports last week indicated that Iran had deployed Revolutionary Guards units to Iraq in order to fight Islamists from the Islamic State of Iraq and the Levant (ISIS), who have taken over several cities in Iraq.

The Pentagon offered no further details on the nature of the Iranians' presence or their operations.

"I'll let the Iranians speak for their activities," Kirby said, adding, "We have indications that there are at least some operatives inside Iraq.”

The rapid offensive by ISIS, which has overrun swathes of northern and central Iraq, has alarmed Tehran - which has close ties to the Iraqi government - as well as Washington.

Western diplomats say Qassem Suleimani, commander of the Quds Force, has traveled to Baghdad to advise Maliki in the crisis.

Iran has previously sent military advisers to Syria to aid President Bashar Al-Assad's regime against rebel forces.

Secretary of State John Kerry said this week that the United States and Iran have a common interest in preventing ISIS militias from taking over Iraq completely, adding that he “wouldn’t rule out” possible cooperation with Tehran on this issue.

Asked about the possibility of working with Iran, President Barack Obama said Thursday that “Iran can play a constructive role if it is helping to send the same message to the Iraqi government that we are sending, which is that Iraq only holds together if it is inclusive.”

He added, If Iran is coming in solely as an armed force on behalf of the Shia, and if it is framed in that fashion, then that probably worsens the situation.”

(Arutz Sheva’s North American Desk is keeping you updated until the start of Shabbat in New York. The time posted automatically on all Arutz Sheva articles, however, is Israeli time.)