Former UN chief weapons inspector Hans Blix warned Friday that North Korea represents the most urgent threat to global nuclear security, and he called on the United States to show more patience in negotiations with Iran. Blix's comments come as North Korea is threatening to test-fire a long-range missile capable of delivering a nuclear warhead, and the United States is insisting on a response by no later than mid-July to a package of incentives for Iran to halt its suspected uranium enrichment program. "To say 'two weeks before a reply has to be given' is not necessary," Blix said. "In the case of North Korea, there are nuclear weapons. That's a more urgent matter." Blix said that North Korea is "a country that feels ostracized" and believes "that nuclear weapons could perhaps protect them in the future, fearing, surely, the United States, which stands there and wags the stick and which says that all options are on the table."