The vice foreign ministers of South Korea, the U.S. and Japan on Monday discussed cooperation on responding to North Korea's latest provocations.

According to the foreign ministry in Seoul, first vice foreign minister Cho Hyun-dong held talks over the phone with U.S. Deputy Secretary of State Wendy Sherman and Japanese vice foreign minister Takeo Mori.

Condemning the North's unprecedented level of recent provocations, the officials agreed that its ballistic missile launches violate multiple UN Security Council resolutions and pose a serious threat to peace and stability on the Korean Peninsula and beyond.

They added that such provocations would further isolate the North and lead to efforts to strengthen the South Korea-U.S. alliance and security cooperation among Seoul, Washington and Tokyo.

The three sides agreed to work closely to send a united message on the North's provocations during upcoming regional gatherings, with the East Asia Summit set to kick off in Phnom Penh on Thursday and the G20 Summit opening in Bali next Tuesday.