UNITED NATIONS - When the UN Security Council meets in emergency session Monday afternoon on North Koreas more powerful nuclear test, it is likely to find it difficult to work out an effective response to the development that has alarmed the east Asian countrys neighbours, diplomats said. They said North Korea is already so isolated there is little left with which to punish the government that has long been willing to take dealings with the outside world to the brink. Issuing condemnations is the easy part, one Asian diplomat said, but agreeing on sanctions is always a problem. It triggers debate over how to balance the punishment so that the civilian population is not affected. Moreover some countries, represented on the council, have lucrative trade ties with Pyongyang and may resist ban on certain items. The 15-member Security Council is set to meet at 4 p.m. Monday (0200 hrs PST Tuesday) at UN headquarters in New York to discuss the crisis. I sincerely hope that the Security Council will take necessary corresponding measures, Secretary General Ban Ki-moon said in Copenhagen, declining to specify what further measures, or sanctions, he would urge the council members to take. Ban, who was in the Danish capital for a global business summit on climate change, said he would closely monitor the meeting in New York. New testing by North Korea would undermine peace and security in the region, Ban said, and he urged the Pyongyang to refrain from taking any actions which will deteriorate the situation. Im deeply disturbed by a report of nuclear testing, he said. If it is confirmed, it is a clear violation of Security Council resolution 1718 of 2006. And it runs counter to the ongoing international communitys efforts to curb nuclear proliferations. North Korea earlier said it carried out a powerful underground nuclear that was much larger than one it conducted in 2006. Russias Defence Ministry confirmed an atomic explosion occurred early Monday in northeastern North Korea and estimated that its strength was similar to bombs that devastated Hiroshima and Nagasaki in the Second World War. The 2006 UN resolution was adopted after North Korea conducted its first nuclear test explosion in October of that year. Ban also said the North Korean test will create negative impact to ongoing negotiation on nuclear disarmament. They should have come to the dialogue table and resolved all the issues through peaceful means, he said. Nuclear testing by North Korea creates tensions in the region and it creates negative impact to regional peace and security. Pyongyang also test-fired three short-range, ground-to-air missiles Monday from the same northeastern site where it launched a rocket last month, South Koreas Yonhap news agency reported, citing unnamed sources. UN resolutions bar North Korea from engaging in any ballistic missile-related activity.