The London Financial Times reported on 13 March that 1,500 fighters controlled by the Tehran-based Supreme Council for the Islamic Revolution in Iraq (SCIRI) arrived the previous day outside a camp new Darbandikhan close to the border with Iraq. The commander of the fighter,s called Abu Thulfaqar, was quoted by the Financial Times as saying that the unit did not come from Iran. 'Turkey is saying we are supported by Iran only to justify its plans to intervene in Iraq,' he was quoted as saying.

SCIRI is an umbrella organisation representing Iraqi Shia parties. It is headed by Mohammad Bakir al-Hakim.

On 11 March, the BBC reported that fighters of the Kurdish Socialist Democratic Party, a Kurdish splinter group, was preparing to attack Kirkuk when the war began. Kirkuk, the principal oil centre in northern Iraq, is controlled by the government of Iraq but claimed by the Kurdish Regional Government (KRG), the coalition administration based in Erbil.