Iraq was massing forces Wednesday for an operation to break a two-month jihadist siege of the Shiite Turkmen town of Amerli, amid growing fears for residents short of food and water. The imminent counter-offensive comes amid reports that US President Barack Obama is weighing a decision to authorise air strikes and aid drops in the area to assist around 12,000 residents trapped in the **rthern town. According to a civilian volunteer commander, thousands of Shiite militiamen from groups including Asaib Ahl al-Haq and the Badr Organisation are gathering in the Tuz Khurmatu area of Salaheddin province, just **rth of Amerli, in preparation for a battle to break the siege. Iraqi aircraft have being targeting positions of Islamic State (IS) jihadists around Amerli, and carried out nine strikes on Tuesday, an ******r said.