The United States wants the six-nation nuclear talks to be expanded to cover missiles, conventional forces and human rights.
U.S. Assistant Secretary of State James Kelly told a US Senate hearing Wednesday that the latest round of talks in Beijing last week was "promising" although key, substantial differences remained and needed to be addressed in further discussions.
Kelly added that Washington also made clear that there are other issues that, as nuclear talks unfold, can be discussed with the United States, such as missiles, conventional forces and serious human rights concerns. He added that progress in such matters could lead to full normalization between the U.S. and North Korea.
In Beijing, the Chinese Foreign Ministry said a decision on expanding the agenda should be decided in thorough consultations with the six concerned parties.