BAGHDAD, Feb 4 (Reuters) - A U.S.-backed Iraqi security plan seen as a last-ditch attempt to halt violence in Baghdad will not produce results overnight, a U.S. general said on Sunday, warning it would take time to bring in reinforcements. Major-General William Caldwell, the U.S. military spokesman in Iraq, was speaking a day after a suicide bomber killed 135 people in the worst single bombing in Iraq since the 2003 war. The attack again turned the spotlight on Prime Minister Nuri al Maliki's much-criticised security sweep in the capital. "It is important to acknowledge that it will not turn the security situation overnight," Caldwell told a news conference in Baghdad. "People must be patient. Give the government and coalition forces a chance to fully implement it. It will take some time for additional Iraqi and U.S. forces to be deployed." U.S. President George W. Bush said last month he was sending 21,500 reinforcements to Iraq, most earmarked for Baghdad, to stem violence between majority Shi'ites and once-dominant Sunni Arabs that has raised fears of an all-out civil war. Referring to the imminent arrival of Lieutenant-General David Petraeus, the new U.S. military commander in Iraq, Caldwell said: "Iraq's problems are systemic and are not likely to be turned around in the first month after his arrival." Caldwell also said that U.S.-trained Iraqi forces had made good progress but that problems remained. "Iraqi security forces have improved measurably. However, Iraqi forces suffer deficiencies in leadership and logistics. It will take more than two months to solve these problems," he said. Maliki, a Shi'ite, last month promised a crackdown in the capital to crush insurgents and militants who have defied attempts by his government to get control of security, but it has not yet begun. Around 1,000 people have been killed across Iraq in the past week in suicide bombings, shootings and fighting between security forces and militants, according to figures compiled by Reuters from official sources.
