“We call on the Shia blocs to reject the election of Mustafa al-Kadhimi and not to be parts of this plans,” the paramilitary said in a statement, calling his designation a betrayal.

Al-Kadhimi emerged as likely prime minister after receiving the support of most of the country’s Shia factions, as well as the Kurdish and Sunni blocs, NRT reported.

Previous prime minister-designate Adnan al-Zurfi stepped aside on Thursday, clearing the way for al-Kadhimi to form a government.

The PM-designate is particularly suspicious of his role as head of Iraq's intelligence agency, which has worked closely with Washington.

The US has carried out a number of airstrikes against Kataib Hezbollah and has accused it of firing rockets at its troops based in Iraq.

Reporter’s code: 50101