Iraq's former premier and current vice president, Nuri al-Maliki, blamed "conspiracies" Saturday for the loss of major cities to jihadists and said Baghdad should prioritise paramilitaries over the army to fight them.

But Maliki, who was prime minister when the Islamic State jihadist group began a brutally effective offensive last year, failed to mention the role he and his government played in the debacle.

"Mosul would not have fallen except for a conspiracy, and Ramadi would not have fallen except for a conspiracy," he said in televised remarks, referring to two major cities lost to IS.

He blamed politicians who opposed him and said a plot to weaken the army was hatched in a neighbouring country, but did not name names.

And he even said that denying the existence of a conspiracy amounts to one: "It is a conspiracy to say that there is not a conspiracy."

Maliki, a Shiite, pursued policies while premier that angered and isolated Iraq's Sunni Arabs, who make up the backbone of IS' support, making it easier for the group to operate and expand.

And as commander-in-chief, he sought to centralise control of the military in his office and played a significant part in its degradation, including by appointing commanders because of loyalty over skill.

On Saturday, he said Iraq should give priority to paramilitaries known as Hashed al-Shaabi, or "popular mobilisation" forces, instead of the army.

"Today, we must focus our effort on the Hashed al-Shaabi until we are liberated and end (IS) and free our lands, and then return to building the army," Maliki said.

Last June, with security forces in disarray and IS advancing toward Baghdad, Maliki announced that the government would arm citizens who volunteered to fight.

Tens of thousands did so, but pre-existing Iran-backed Shiite militias were the core of that force, and continue to be.

They helped stop the IS advance and were later central to operations that retook one province and large parts of another from the jihadists.

But the power of the militias is also a threat to the Iraqi state, which claims to command them but does not control them, and they could also eventually turn on each other.

Brit, German among bombers in deadly Iraq attack
Baghdad (AFP) June 13, 2015 - At least 11 Iraqi security personnel were killed Saturday in a quadruple suicide car bombing near Baiji that the Islamic State group said four of its foreign fighters carried out.

Police and army sources said the four car bombs were unleashed on security targets in Hajjaj, which lies on the road between Tikrit and Baiji in Salaheddin province, north of Baghdad.

Seven soldiers were killed as well as four members of the Popular Mobilisation force, an umbrella for mostly Shiite militias and volunteers that has been doing much of the heavy lifting in the fight against IS in Iraq.

At least 27 people were also wounded in the coordinated attack, which saw one of the four car bombs neutralised before it could reach its target, a police colonel said.

An army officer said the vehicles used were identical, brand new SUVs that looked like an official convoy.

Pictures released by IS show the black-clad suicide bombers each standing by one of four black Toyota Land Cruisers.

IS said in a statement that the bombers were a Kuwaiti, a Palestinian, a Briton and a German.

The picture of the German bomber, named Abu Ibrahim al-Almani, shows a red-haired blue-eyed man behind the wheel of his explosives-laden car, smiling and pointing his index finger to the sky.