South Korea's foreign minister urged the international community Thursday to send a clear and strong message against North Korea's nuclear weapons development as the communist country boasted the successful launch of an intermediate-range ballistic missile earlier this week.

Foreign Minister Yun Byung-se made the call in his first public comments since North Korea launched two Musudan missiles Wednesday, one of which flew 400 kilometers before landing in targeted waters in the East Sea.

The North has pursued missile and nuclear development in tandem, vowing to build nuclear-tipped ballistic missiles capable of reaching the U.S. mainland.

"The NSG needs to send a clear, loud and powerful message against North Korea's nuclear weapons programs, the number one threat to the international non-proliferation regime at this critical juncture," Yun said in an address before the 48 member nations of the Nuclear Suppliers Group, which seeks to support the non-proliferation regime through controls on the exports of nuclear material.

"As long as North Korea continues to defy the non-proliferation regime, we, the whole world, should remind North Korea that its misbehavior will have unbearable costs," he said. (Yonhap)