Iran's regional proxy network has come under unprecedented pressure since the war in Gaza began, with leaders and officials being killed in targeted Israeli attacks over the past year.
Iran-backed militias in Iraq have been discussing future roles amid pressure to disarm, said an Iraqi source close to the Popular Mobilisation Forces (PMF), a coalition of militias dominated by groups with ties to Iran.
The militias are part of the Islamic Resistance in Iraq, an umbrella group of about 10 hardline Shiite armed factions that collectively command about 50,000 fighters and arsenals that include long-range missiles and anti-aircraft weapons, according to two security officials who monitor militias' activities.
The Resistance group, an important pillar of Iran's network of regional proxy forces, have claimed responsibility for dozens of missile and drone attacks on Israel and US forces in Iraq and Syria since the Gaza war erupted about 18 months ago.
"All previous governments, since the formation of the PMF by decision of the Shiite religious authority, have been subject to pressure to restrict arms to the state," the source said.
Here are the Iran-backed militias you need to know about:
Kataib Hezbollah
Kataib Hezbollah (Hezbollah Brigades) was founded in the aftermath of the 2003 US-led invasion of Iraq and is one of the elite Iraqi armed factions closest to Iran. It is the most powerful armed faction in the Islamic Resistance in Iraq, and has claimed hundreds of attacks on US forces since the Gaza war began.
After its founding, the group quickly developed a reputation for deadly attacks against military and diplomatic targets in the 2000s, using a mixture of sniper, rocket and mortar attacks and roadside bombs.
The US designated it as a terrorist organisation in 2009. It was led by dual Iraqi-Iranian citizen Abu Mahdi Al Muhandis until he was killed in a US drone strike at Baghdad International Airport in 2020, along with Iranian Quds Force commander Qassem Soleimani.
It views US troops in Iraq as foreign occupiers and has called for their forceful expulsion. The US has struck Kataib Hezbollah positions, bases and training and logistics hubs several times over the years.
The group fought alongside other Shiite militias against mostly Sunni rebels during Syria's civil war and has continued to operate in Syria since.
Kataib Hezbollah has thousands of fighters and an arsenal of drones, rockets and short-range ballistic missiles, Iraqi officials and members of the group say.
Al Nujaba Movement
The Al Nujaba Movement (or Hezbollah Al Nujaba) is led by Akram Al Kaabi, who after 2003 was part of the Jaish Al Mahdi militia, before joining Asaib Ahl Al Haq and then travelling to Syria to establish Al Nujaba in around 2013. By 2014, many of its personnel had returned to Iraq and joined the new PMF movement.
In 2008, the US Treasury sanctioned Al Kaabi for involvement in attacks against the US-led coalition.
In 2019, the US State Department designated Al Nujaba as a terrorist group.
Sayyed Al Shuhada
Kataib Sayyid Al Shuhada (KSS, Battalion of the Master of Martyrs) is an Iraqi Shiite paramilitary group formed in 2013. It is funded, trained and equipped by the IRGC's Quds Force and Hezbollah.
The group has been described as an Iranian proxy, and is one of the original militias that formed the PMF in 2014.
It was also active in Syria, where its main focus was the protection of the Sayyidah Zaynab Mosque in a southern suburb of Damascus. It militarily supported the Syrian government and participated in the Syrian civil war.
On November 17, 2023, the US government designated KSS as a foreign terrorist organisation.
Asaib Ahl Al Haq
A splinter of Moqtada Al Sadr’s Jaish Al Mahdi militia that broke away in 2005-2006 with support from Iran's Islamic Revolutionary Guard Corps-Quds Force (IRGC-QF) and Lebanese Hezbollah.
Formed to undertake anti-US operations in Iraq under the leadership of senior Sadrist religious student Qais Al Khazali, his brother Laith Al Khazali, and Sadrist commander Akram Kaabi.
The group undertook a January 2007 attack on the US base at the Karbala police centre that resulted in the kidnapping and murder of five American soldiers. Qais and Laith Al Khazali were detained by the US-led coalition from 2007 to 2010, until their release was brokered for the return of a Western hostage and the bodies of executed Britons.
After the US withdrawal in 2011, the group tightened its ties to the IRGC-QF’s axis of resistance and sent a contingent to fight in the Syrian civil war under the IRGC-QF's operational control.
After 2014, Asaib Ahl Al Haq became a central component of the PMF, while facing accusations that it had committed human rights violations against Sunnis.
In January 2020, the group was designated by the US as a terrorist organisation. Also in the same year, Qais and Laith Al Khazali were put on a terror list.
Imam Ali Brigades
Imam Ali Brigades was established in June 2014 under the leadership of Shibl Al Zaidi, a former Mahdi Army commander. In the war against ISIS, the group deployed forces in Iraq (beginning in 2014) and Syria (2015).
The US Treasury designated Al Zaidi as a terrorist in 2018 for allegedly acting as a financial co-ordinator between the Quds Force, Iraqi paramilitaries and Lebanese Hezbollah.
It established the Professionals for Reconstruction Party, winning one seat in the 2018 elections, when it also joined the Al Fatah coalition.
As of 2018, Imam Ali Brigades had an estimated 7,000 fighters, although it has reportedly become less active as a paramilitary force since around 2020.
Jund Al Imam (Soldiers of the Imam)
The group was originally formed as a militia during the 1991 Iraqi uprisings, with help from Iran. The group came back to prominence after regrouping in Iraq to fight against ISIS in 2014, when it participated in the liberation of Jurf Al Sakhar, helping take back control of the area from the group.
In 2017, the group, along with six other groups, formed the PMF.
Ansar Allah Al Awfiya
Initially emerged as a political group in 2013 under the name Kayan Al Sidq Wal Ataa (Entity of Honesty and Giving). In 2014, it joined the PMF under the name Ansar Allah Al Awfiya. It has also reportedly been active in Syria.
Some media outlets blamed the group for killing dozens of Syrians in Deir Ezzor province in 2021. The US accused Ansar Allah Al Awfiya of killing of three US servicemen in January 2024 and designated it as a terrorist group.
In the 2018 election, the group aligned itself with the Fatah coalition.
Since 2023, the group claimed attacks on Israel, most of which have not been verified.
