South Korea on Wednesday called for a stronger international stance against North Korea's nuclear threats after Pyongyang said it will not be returning to the negotiating table with the United States. South Korean President Park Guen Hye said in a meeting with foreign ambassadors in Seoul that North Korea must not be rewarded for its "bad behaviour," the Yonhap News Agency reported. "We must break the vicious cycle of holding negotiations and providing assistance if (North Korea) makes threats and provocations, and again holding negotiations and providing assistance if there are threats and provocations," Park was quoted as saying in the meeting.