US doesn't see 'any prospect' for diplomatic breakthrough as North Korea plays 'game of risk'

The delegation included White House point-man on North Korea policy Sydney Seiler and the State Department's envoy to the six-party talks about the country's nuclear program, Clifford Hart.

Davies said the nations he visited were on the same page.

“Of course, we discussed sanctions in South Korea, we discussed sanctions in Beijing, and we discussed sanctions here [in Japan],” he said. “And we agreed in all three capitols that it's very important that we fulfill the sanctions commitments contained in the recently passed United Nations Security Council resolution. Only by doing that can we prevent North Korea from obtaining the materials it needs to carry forward its weapons of mass destruction program, and prevent North Korea from proliferating technologies that are dangerous to the entire world.”

North Korea has previously conducted nuclear weapons tests in 2006 and 2009. In December, the country successfully launched a rocket that could put the United States within range of its weapons program.