America and its allies has been forced to form a closer co-operation with Iran's favoured Shia militias in battle for Baiji. America and its allied jets has been providing air cover for the coalition of Iraqi forces and the dreaded Iran suppoted Shia militias. Coalition jets have joined in to bomb Islamic State of Iraq and the Levant positions,official statements from Pentagon and the troops say. Members of the Imam Ali Brigade are fighting along side US-trained Iraqi special forces in the battle for the oil refinery city of Baiji. It has been a tough battle between the coalition-allied forces and the insurgents in and outside the refinery compound and in the surrounding desert. Baiji city lied on the road from Bagdhad north to Monsul and was seized by Isil last June as they swept through the central and north of Iraq. Towards the end of last year,the army retook parts of the city,but was again sent out in an Isil counter-attack.Whicharmy special forces and Shia militias now managed to breakthrough.