Nuclear envoys from Japan, the United States and South Korea have reaffirmed the importance of holding a "credible dialogue" with North Korea to wind down its nuclear program, a step that could lead to the resumption of the long-stalled six-party talks.

"We affirmed that before resuming the six-party talks, it is important that North Korea express its commitment toward denuclearization in a concrete manner," Junichi Ihara, director general of the Asian and Oceanian Affairs Bureau of the Foreign Ministry, said after a trilateral meeting in Tokyo on Wednesday.

Ihara said the regional powers could hold a credible dialogue with North Korea bilaterally or multilaterally.