The UN Security Council unanimously passed a resolution yesterday expanding sanctions against North Korea as punishment for its December rocket launch, and Pyongyang did not take the news lying down. It responded angrily today by promising to strengthen its nuclear weapons program and suggesting it would carry out a third nuclear test: "There can be talks for peace and stability of the Korean Peninsula and the region in the future, but no talks for the denuclearization of the peninsula," it said in a statement, adding that it will take "physical counteraction." Analysts say that most likely means another test, the New York Times reports. South Korea has increased monitoring of the North Korean test site since the declaration, Yonhap News reports.
Underground nuclear tests were conducted at the Punggye-ri nuclear test site in 2006 and 2009 (both as the country protested UN sanctions), and experts have this year pointed to movement indicating North Korea is prepping the site. The biggest question: Whether a new test will involve a uranium device. The last two used plutonium bombs, but Pyongyang has recently been increasing its efforts to enrich uranium. Under the UN resolution, which was backed by North Korea-ally China, more groups (like the North Korean space agency and a bank) and individuals were added to sanctions lists, the BBC reports. Yonhap News adds that South Korea and the US may impose their own additional sanctions, like beefing up ship inspections. (Read more North Korea stories.)