Coalition air strikes are needed to retake Tikrit, where die-hard jihadists are defending their last redoubt with trenches, sandbags and roadside bombs, Iraqi officers said on Sunday.
Two weeks into Baghdad's biggest operation yet against the Islamic State (IS) group, Iraqi forces have a complete stranglehold on the city but are unable to launch a final assault, they said.
Staff Lieutenant General Abdulwahab al-Saadi said he had asked the defence ministry to request coalition involvement but "no air support" from foreign allies had yet been provided.
"They are able to locate the targets exactly" and carry out accurate strikes, he told AFP in an interview at Tikrit University on the northern edge of the city.
Fighters from the Imam Ali Brigade, a Shiite militia involved in the Tikrit operation, complained to AFP that a Sukhoi jet had even bombed pro-government forces by mistake.
"We are reinforcing our offensive capacities in the areas we have cleared and reinforcing our control on the entrances to the city," an army major general said Sunday.
But the Iraqi army was mostly less upbeat, with one senior officer saying he could envision the battle of Tikrit lasting two more weeks.
Iran involvement
Shiite Iran has been Baghdad's main foreign partner in the operation and Tehran's top commander in charge of external operations, Qassem Soleimani, has been omnipresent on the front lines.
Coalition air strikes have supported several other operations to reclaim jihadist-held territory in Iraq in recent months, including some in which Iran-backed Shiite militias were involved.
Iraqi security forces, backed by Shiite volunteers and militias, and in some cases Sunni tribesmen opposed to IS, have in recent months been working their way north.
In October, they retook Jurf al-Sakhr, the southernmost area to have been captured by IS, and have since also reclaimed the eastern province of Diyala.
Iranian support was crucial in both those operations. Kurdish peshmerga have also been pushing back jihadists from northern parts of the country, with US-led coalition support.
The last remaining IS stronghold east of the Tigris river is Hawijah, a city northeast of Tikrit, where fleeing jihadists are believed to have gathered and on which Kurdish forces are advancing.
Tikrit is seen by commanders as a key stepping stone on the way to reconquering IS's northern hub of Mosul, Iraq's second city.
The outcome of the battle seems in little doubt but there is more at stake for the government than just territorial gain.
The vast operation is seen as a test of Baghdad's ability to instil discipline in the array of fighting forces involved in the anti-IS war and prevent some of the abuses committed in past operations.
Tens of thousands of people have been displaced by the offensive. Tikrit once had an estimated population of 200,000 but it is unclear how many civilians remain in the war-torn city.
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