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WASHINGTON, June 15 (Reuters) - The United States is preparing to open a direct dialogue with longtime adversary Iran on security in Iraq and ways to push back Sunni militants who have taken over large areas of the country, the Wall Street Journal reported on Sunday.
Citing senior U.S. officials, the newspaper said the dialogue was expected to begin this week. It comes as the United States and other world powers strive for an agreement with Tehran to curb its nuclear program.
Militants from the Islamic State of Iraq and the Levant group have swept through towns in the Tigris valley north of Baghdad in recent days but appeared to have halted their advance outside the capital on Sunday as they tightened their grip on the north.
U.S. officials said it was not certain which diplomatic channel the Obama administration would use to discuss Iraq, the Journal reported. One possibility was through Vienna, the paper said, where senior U.S. and Iranian officials were scheduled to meet with other world powers on Monday to negotiate limits on Iran's nuclear capabilities.
The State Department said on Sunday that the No. 2 U.S. diplomat, Deputy Secretary of State Bill Burns, would travel to Vienna this week to take part in the talks.
U.S. Senator Lindsey Graham said on Sunday that Washington needed Iran's involvement to prevent a government collapse in Iraq and should open talks with Tehran.
"We are probably going to need their help to hold Baghdad," Graham, a South Carolina Republican, said on CBS' "Face the Nation." (Reporting by Jim Loney; Editing by Peter Cooney)