U.S. President George W. Bush promised Wednesday to «stay on the offense» in Iraq to prevent insurgents from disrupting next week's referendum on a new constitution, AP reported. His spokesman also welcomed Iraq's decision to back away from last-minute election rules changes that the United Nations said were unfair. «We fully understand they intend to disrupt the constitutional process, or will try to do so, as well as stop the progress of democracy,» Bush said of the insurgents after a briefing at the White House from Defense Secretary Donald H. Rumsfeld and other Pentagon officials. «The Iraqis are showing more and more capability of taking the fight to the enemy,» the president told reporters. «Our troops will stay there as long as necessary. As they become more capable, we will be able to bring folks home,» he added.