Iranian-backed militias that are designated as terror organizations by the U.S. government are increasingly taking charge of the battle against the Islamic State of Iraq and Syria (ISIS) in Iraq in the wake of the fall of the city of Ramadi, The Washington Post reported Saturday.

Iraq’s two main allies — Iran and the United States — have vied for influence over Iraq’s battle to retake ground from Islamic State militants in the past year. While Iranian-linked Shiite militias have spearheaded the fight elsewhere, the U.S.-backed Iraqi army and counterterrorism units had been on the front lines in Anbar province, supported by an eight-month American-led air campaign.

But with the fall of Ramadi, the province’s capital, this month, paramilitary forces close to Iran are now taking the upper hand. They include groups such as Kitaeb Hezbollah, responsible for thousands of attacks on U.S. soldiers who fought in Iraq after the 2003 invasion.

An Iraqi general quoted in the article said that government forces, backed by the United States, are fighting “side by side” with Iranian-backed militias like Kitaeb Hezbollah, a designated terror organization.

The fall of Ramadi and the assertiveness of the Iranian-backed militias has hurt America’s standing in Iraq, according to observers.

U.S. credibility had risen in Iraq when Islamic State forces were driven from the city of Tikrit earlier this year, thanks in part to coalition airstrikes, Kenneth Pollack, a Middle East expert at the Brookings Institution, noted in a recent article. But the fall of Ramadi has damaged Iraqis’ confidence in the United States, he said. If Shiite militias play a role in retaking Ramadi, “that can only bolster Tehran’s influence in Baghdad at the expense of Washington’s,” he wrote.

Last week, Israeli Defense Minister Moshe Yaalon said that Iran had no interest in a stable Iraq, and observed that Iran has been working against stability in its neighbor since 2003. Yaalon’s comments came amid reports that Iranian-backed militias were taking charge of the fight against ISIS in Iraq. Yaalon’s remarks echoed those of analyst and former U.S. Army intelligence officer Michael Pregent, who wrote earlier this month that “Iran needs the threat of ISIS and Sunni jihadist groups to stay in Syria and Iraq in order to become further entrenched in Damascus and Baghdad.”

[Photo: Stahlgewitter Syrien / YouTube]