North Korea has dismissed calls by the United States for it to declare its nuclear activities as soon as possible, describing the calls as just "a mere hope."

Radio Free Asia on Monday quoted North Korean Ambassador to the U.N. Pak Gil-yon as saying that his country had fully disclosed its nuclear activities to the U.S.

The statement comes a week after U.S. nuclear envoy Christopher Hill called upon the North to make its nuclear declaration within the month.

The North Korean ambassador said that agreements reached at two inter-Korean summits should be implemented even if a new government has taken office in the South.

He added that his country will watch actions taken by South Korea's new President Lee Myung-bak.

The North Korean envoy blamed the U.S. for delays in the six-party process, claiming that Washington has not offered heavy fuel oil promised under a related series of six-party accords. He said Pyongyang has done its part and that the nuclear problem will be resolved only when the U.S. keeps its promises.