BAGHDAD, Nov 30 (Reuters) - US air support and pledges of weapons and training for Iraq's army have raised expectations of a counter-offensive soon against Islamic State, but sectarian rifts will hamper efforts to forge a military strategy and may delay a full-scale assault.
The Sunni Islamists stormed through northern Iraq in a 48-hour offensive in June, charging virtually unopposed towards the outskirts of Baghdad, humiliating a US-trained Iraqi army which surrendered both land and weapons as it retreated.
By contrast, even a successful effort by the Shi'ite-led government to dislodge Islamic State, also known as ISIS, from Sunni territory where it rules over millions of Iraqis would be fiercely fought and could stretch well beyond next year.
The Baghdad government relies on Shi'ite militias and Kurdish peshmerga to contain Islamic State - a dependence which underlines and may even exacerbate the sectarian rivalry which opened the door for the summer offensive.
US newspapers have cited officials in Washington saying the Americans' training mission aims to prepare Iraqi troops for a spring offensive to retake territory, including Mosul, northern Iraq's largest city and Islamic State's powerbase.
Hemin Hawrami, an official close to Kurdish leader Masoud Barzani, told Reuters that Iraqi forces would not be ready to take the fight to Mosul, in Iraq, until late 2015. "There will be no spring or summer (offensive)," he said, adding that progress depended on government willingness "to reorganise the army, how quickly they can solve political issues with us and the Sunnis, (and) how quick the coalition will be in providing heavy arms to peshmerga and the Iraqi army."
The army, Shi'ite militias and Kurdish fighters have made some gains against Islamic State, pushing back an advance towards Kurdish territory in August and last week recapturing towns in Diyala province, on the road from Baghdad to Iran.
The leader of the pro-Iranian Shi'ite Badr Organisation, whose fighters battled alongside peshmerga and soldiers in Diyala, said they would turn next to the Sunni provinces of Salahuddin and Anbar - north and west of Baghdad - before moving further north to Nineveh province, where Mosul lies. "We are counting on the support of the Sunni tribal fighters. With them joining the fight, our victory is certain,"Hadi al-Amiri told Reuters by telephone from Diyala province.
Amiri said he expected to get weapons not just from the Iraqi government, which may allocate a quarter of next year's $100 billion budget to the military, but also from the $1.6 billion of arms and training which Washington plans to deliver.
Both Amiri's assumptions look optimistic, as Washington and the Sunni tribes are deeply wary of Shi'ite militia forces.
Iraqi authorities aim to overcome the deep rifts between Shi'ites, Sunni Arabs, Kurds and other groups by absorbing local fighters into a state-funded National Guard, but the role of that force remains undecided.