North Korea's demands for what it should receive in exchange for abandoning its nuclear weapons program snarled talks Sunday, but the U.S. envoy maintained that "things are moving," with more negotiations planned Monday. The negotiations ended their sixth day without an agreement on a Chinese-drafted proposal, and South Korean Deputy Foreign Minister Song Min-soon said talks Sunday focused on "what corresponding measures other parties will take" in return for an agreement by the North to dismantle its nuclear weapons program.The North has demanded concessions such as security guarantees and aid from Washington before it eliminates its weapons program, while the United States wants to see the arms destroyed first. The North has also insisted that it be allowed to run a peaceful nuclear power program, something Washington objects to out of proliferation concerns.