HILLA, IRAQ - Clashes between security forces and militants near the Iraqi capital killed 20 security personnel on Saturday, an army officer and doctors said. The fighting in three areas southwest of Baghdad also wounded 22 members of the security forces.Iraqi government forces backed by helicopter gunships began an offensive on Saturday to retake the northern city of Tikrit from Sunni Islamist militants while party leaders pursued talks that could end Prime Minister Nouri al-Maliki’s divisive rule. Politicians in Baghdad and world powers warn that unless security forces recover cities lost to the jihadi insurgents in tandem with a rapid formation of a government that can bring Iraq’s estranged communities together, the country could rip apart along sectarian lines and menace the wider Middle East. On the battlefield, Iraqi troops were trying to advance on Tikrit from the direction of Samarra to the south that has become the military’s line in the sand against a militant advance southwards to within an hour’s drive of Baghdad.Iraqi special forces already have snipers inside Tikrit University who were dropped by air there in a bold operation on Thursday. Helicopter gunships fired at targets in Tikrit on Saturday and ISIL fighters abandoned Tikrit’s governorate building, security sources said. More government troops had been air-dropped in a pocket just north of the city. Iraqi military spokesman Qassim Atta told reporters in Baghdad on Saturday that 29 ‘terrorists’ were killed on Friday in Tikrit and that militant commanders were struggling because ‘their morale has started to collapse.’However, the militants were showing resilience and enjoyed the backing of some local Sunni tribes, as well as former ruling Baathists from the era of late Sunni dictator Saddam Hussein - whose hometown was Tikrit - alienated from Maliki’s government. Since early June, the radical ISIL have overrun most majority Sunni areas in the north and west of Iraq, capturing the biggest northern city Mosul and fanning southwards. ISIL vows to re-create a medieval-style caliphate erasing borders from the Mediterranean to the Gulf and they deem all Shi’ites to be heretics deserving death. They boast of executing scores of Shi’ite government soldiers captured in Tikrit.In a stunning political intervention on Friday that mean the demise of Maliki’s eight-year tenure, powerful Shi’ite cleric Grand Ayatollah Ali Sistani urged political blocs to agree on the next premier, parliament speaker and president before a newly elected legislature meets in Baghdad on Tuesday. Saudi King Abdullah pledged in talks with US Secretary of State John Kerry to use his influence to encourage Sunni Muslims to join a new, more inclusive Iraqi government to better combat Islamist insurgents, a senior US official said on Saturday.Abdullah’s assurance marked a significant shift from Riyadh’s unwillingness to support a new government unless Maliki, a Shi’ite, steps aside, and reflected growing disquiet about the regional repercussions of ISIL’s rise. ‘The next 72 hours are very important to come up with an agreement to push the political process forward,’ said a lawmaker and former government official from the National Alliance, which groups all Shi’ite Muslim parties.The lawmaker, who asked for anonymity due to political sensitivities, said he anticipated internal meetings by various parties and a broader session of the National Alliance including Maliki’s State of Law list to be held through the weekend. Some Sunni Muslim parties were to convene later on Saturday. Iraqi Sunnis accuse Maliki of freezing them out of any power and repressing their community, goading armed tribes to support the insurgency led by the fundamentalist Islamic State in Iraq and the Levant group (ISIL). The president of Iraq’s autonomous Kurdistan region has also said Maliki should bow out.Sistani’s entry into the fray will make it hard for Maliki to stay on as caretaker leader as he has since a parliamentary election in April. That means he must either build a coalition to confirm himself in power for a third term or step aside. Sistani’s message was delivered after a meeting of Shi’ite factions including the State of Law coalition failed to agree on a consensus candidate for prime minister. Maliki, whose State of Law coalition won the most seats in the April election, was positioning himself for a third term before the ISIL offensive began. His closest allies say he still aims to stay, but senior State of Law figures have said he could be replaced with a less polarising figure.