Afghanistan has defied the Bush administration and signed a new international ban on cluster bombs. The last-minute decision came as more than ninety other governments also ratified the treaty Wednesday in Oslo. The US has led a group of large nations refusing to adopt the ban. It bars use, stockpiling and trading of cluster weapons and requires signatories to clear contaminated areas within ten years. The White House reportedly urged Afghan President Hamid Karzai not to sign the treaty. Thomas Nash of the Cluster Munition Coalition welcomed the new signatories.