The White House said Thursday it was committed to addressing concerns about cluster bombs but refused to sign a new global ban on their use because of “disagreements” on how to solve the problem. Officials from 111 countries on Wednesday agreed on a wide-ranging deal to outlaw the use, production, transfer, and stockpiling of cluster munitions. The United States, China, Russia, India, Pakistan, and Israel did not participate. “The United States is deeply concerned about the humanitarian impact not only of just cluster munitions but really the whole range of munitions that are used in war,” Scott Stanzel, a White House spokesman, said in a statement given to reporters traveling in Utah with President George W. Bush. Stanzel said it was an “absolute moral obligation” to clean up undetonated munitions after a conflict to protect civilians and said the United States had spent more than $1.2 billion on such activities since 1993. “Now we are very strongly committed to work to address this problem, but we may have some disagreements about the right venue and the right tactics to follow in trying to solve the problem,” the statement said. Cluster munitions pose grave dangers to civilians during and after conflicts. Many civilians have been killed or maimed by their wide area effect and unexploded bomblets detonating long after their first use.