Speaking to reporters in Seoul, where he arrived after visiting China, Davies responded to questions about restarting the stalled talks on ending North Korea's nuclear weapons program in return for substantial aid. The talks, which include the two Koreas, China, Japan, the United States and Russia, broke off in 2009 after the North unilaterally chose to end them.
Davies met with the reporters after talks with his South Korean counterpart Cho Tae-yong, Yonhap News reported.
"What we need is not just change in attitude, but change in direction, in fact, concrete steps from North Korea," Davies said. "But so far, North Korea has been a no-show on nuclear issues."
The U.S. official said North Korea must show sincerity in implementing its promise made in September 2005 to discard its nuclear program in return for international energy and other aid. However, since then the country has conducted three nuclear bomb tests, which were also in violation of United Nation resolutions banning such activities.
The steps demanded by the United States and South Korea include the North placing a moratorium on its nuclear program, halting atomic and missile tests, ending its uranium enrichment and allowing international inspectors to make on-site inspections.
China, North Korea's main ally, has been seeking to restart the talks even as the isolated country, under its unpredictable leader Kim Jong Un, has continued with nuclear and missile tests and other provocations, escalating tensions on the Korean Peninsula.
"We will have to make sure North Korea's leadership will change strategic calculation and find that possessing nuclear weapons is not actually in his strategic interest," Cho said. "Our two countries will keep working on a number of initiatives and efforts so that we will be able to have the six-party talks back on solid ground."
Davies, who will also visit Japan on his Asia trip, comes to the region after a recent visit by U.S. Deputy Secretary of State William Burns who also discussed the denuclearization issue. U.S. Secretary of State John Kerry is expected to visit the region next month.