Top nuclear envoy Kim Gunn held separate phone talks with his U.S. and Japanese counterparts following North Korea's ballistic missile launch on Saturday.

Seoul's foreign ministry said Kim talked on the phone with U.S. Special Representative for North Korea Sung Kim and Japanese foreign ministry director-general for Asian and Oceanian Affairs Funakoshi Takehiro.

The envoys denounced Pyongyang's fourth provocation in less than a week, saying the missile launches pose a grave threat to the Korean Peninsula and the entire world.   

They also criticized the regime for squandering resources on missile tests despite its struggling economy, and agreed to maintain close bilateral and trilateral communication and seek a united response from the global community.