U.S. Secretary of State Mike Pompeo urged Japan and South Korea on Thursday to find ways to defuse heightened tensions between the key American allies over wartime history and trade policy.

"We hoped that they will find a way to move forward together," Pompeo told reporters in Bangkok after Japanese Foreign Minister Taro Kono and his South Korean counterpart Kang Kyung Wha apparently failed to bridge wide differences in their positions when they met earlier in the day.

Pompeo said he briefly met with Kono before they have a trilateral meeting Friday with Kang on the sidelines of Association of Southeast Asian Nations-related foreign ministerial meetings in the Thai capital.

Pompeo criticized Chinese "coercion" in the South China Sea, alluding to Beijing's recent actions in disputed waters such as test-launching anti-ship ballistic missiles.

The chief U.S. diplomat also said he regrets not having talks with North Korean representatives while in Bangkok because the North's Foreign Minister Ri Yong Ho will skip the ASEAN Regional Forum, a 27-member security meeting on Friday.

However, Pompeo said, "We stand ready to continue our diplomatic conversations with the North Koreans."

Pompeo said he has urged regional allies "to maintain the sanctions that spur diplomacy with North Korea, to speak out against Chinese coercion in the South China Sea," and to deal effectively with other pressing issues.

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