"The difficulties that have currently arisen are temporary and can be surmounted," the North Korean leader said, according to China's Xinhua news agency.
North and South Korea, the United States, China, Japan and Russia reached a disarmament deal last year that set an end of 2007 deadline for the North to fully declare its nuclear activities in exchange for fuel aid and political concessions.
"As long as all the parties... adhere to their promises, the talks can overcome obstructions and constantly advance"
North Korean leader
Wang used the rare meeting in Pyongyang on Wednesday to call on North Korea and the other countries to push forward the stalled deal.
The North began dismantling its Yongbyon nuclear plant in November and says it gave a full declaration of all its nuclear programmes in the same month as part of the deal.
But the US has repeatedly said that Pyongyang has not submitted a "complete and correct" list of all its nuclear programmes.
Wang's meeting with Kim came ahead of the arrival in the North Korean capital of the US state department's trop Korean affairs expert, hoping to push the deal forward.
In talks with the Chinese envoy, the North Korean leader indicated that he wanted the other parties to do more in implementing the agreement, but the report did not spell out specific demands.
"As long as all the parties follow the principle of action-for-action and conscientiously adhere to their promises, the talks can overcome obstructions and constantly advance," Kim was quoted as telling the envoy.
If North Korea makes an acceptable nuclear declaration, the United States is expected to ease trade restrictions and take it off a blacklist of states that it says sponsor terrorism.