Iraqi forces are moving into position to take over the security of Iraq’s city centres as US troops prepare withdraw six years after the invasion that toppled Saddam Hussein.Security has been tightened in anticipation of the pullback, which is being seen as a milestone on the country’s road to sovereignty. “Of course today is a celebration for us and for all Iraqis”, said one Iraqi policeman. “After the withdrawal of US forces our main duty, the main job of the Iraqi forces, including the police and army, will start.” All leave has been cancelled for Iraqi police who have been put on high alert for the withdrawal of US combat forces. In the main cities and two sunni dominated provinces in grey Iraqi police and army will be in command of security. In the white there will just be police. US forces will remain stationed in barracks outside the main cities. “Iraqis are capable and ready to maintain security when the Americans withdraw and God willing we are brothers and there is no difference between Shi’ites and Sunnis. We are very happy.” The security of Iraq’s oil pipelines, installations and terminals will be occupying the minds of the world’s biggest oil firms. They are due to bid on Tuesday for Iraq’s main oil and gas fields. They are unlikely to rely on Iraqi forces for security, however, and are expected to hire their own security firms.