One of Iraq's main Shi'ite political blocs has rejected Prime Minister Nuri Al-Maliki's claim to a second term and halted government formation talks until his party nominates a new candidate, politicians said. Though expected, this is a major setback in the process of forming a new government at a time when civilian deaths are rising and US troops are planning to halt combat operations. Almost five months after Iraq held a parliamentary election meant to set it on a course toward stability after years of war, sanctions and insurgency, Iraqis are no closer to knowing who their next prime minister will be. Maliki's State of Law bloc, which came second in the March 7 parliamentary election, and the third-placed Iraqi National Alliance (INA), announced their merger in June under a new name, National Alliance. Together the merged Shi'ite coalition has 159 seats in the new 325-seat parliament, four short of a majority. But the prime minister's post remains a stumbling bloc and talks to form a government have gone nowhere because of discord over Maliki's desire for a second term. “All parties of the INA have agreed that the obstacle is the insistence of nominating Maliki,” Qusay Al-Suhail, a senior member of the Sadrists political movement, a main faction of the INA, said Sunday. “That is why we demanded an alternative ... The INA's decision is unanimous.” On Saturday, Ahmed Chalabi, a veteran politician and member of the INA, said the Shi'ite merger is sticking together but left the door open for talks with other political blocs. “We stress our adherence to the National Alliance as the biggest parliamentary bloc,” Chalabi told a news conference, which was attended by representatives from the INA.