Japan says a Chinese envoy's visit to North Korea has not changed the situation on Pyongyang's nuclear program, and will act against the North as planned.

The possibility of resolving the problem diplomatically has loomed since high-ranking Chinese official Tang Jiaxuan went to Pyongyang Thursday for talks with North Korean leader Kim Jong-il.

A Japanese Foreign Ministry official said Tang's visit has postponed additional nuclear tests, but that the overall picture has not improved as Pyongyang insists on returning to the six-way talks only if U.S. financial sanctions against it are lifted.

On a possible delay in sanctions against the North to resume the talks, Japanese Prime Minister Shinzo Abe urged Pyongyang to observe the U.N. resolution without precondition.

He said the North should understand that the situation will worsen unless it accepts the request of the international community.