North Korea is reportedly readying a test of an intermediate-range ballistic missile, according to South Korea's Yonhap news agency. That report comes after Pyongyang conducted a series of tests, including a reported nuclear bomb test in January and a long-range rocket in February. The nuclear test drew international condemnations and fresh U.N. economic sanctions.
Last month, the United States and South Korea began talks over the potential deployment of Terminal High Altitude Area Defense on the peninsula.
Obama told interviewer Charlie Rose that North Korean leader Kim Jong Un is "personally irresponsible" and that "we don't want them to get close, but it's not something that lends itself to an easy solution."
The president added that "we could obviously destroy North Korea with our arsenal, but aside from the humanitarian costs of that, they are right next door to our vital ally" South Korea.
The Obama administration has sought to persuade China to exert greater pressure on Pyongyang, and Beijing supported the U.N. sanctions.
Obama said Beijing tends to view regional issues and disputes as a "zero-sum game," adding that the Asian power bullies its neighbors in the South China Sea.
"Rather than operate under international norms and rules, their attitude is, 'We're the biggest kids around here, and we will push aside the Philippines or the Vietnamese," Obama said. "That doesn't mean we are trying to act against China. We just want them to be partners with us. Where they break out of international rules and norms, we will hold them to account."