The United States is considering establishing a new framework to boost nuclear deterrence against North Korea with Japan and South Korea, sources with knowledge of the plan said Wednesday.

The U.S. government has already sounded out its two major Asian allies about the idea, which comes as North Korea ramps up its development of long-range missiles and nuclear weapons, according to the sources.

Japan is poised to accept the U.S. proposal, the sources said, while South Korea is believed to be ready to do the same.

The United States already regularly discusses "extended deterrence" relying on its nuclear forces and conventional military capabilities with the two countries bilaterally. But there has been no trilateral framework for U.S. officials to do the same.

"We're in discussions now about new mechanisms and new consultative mechanisms to get after some of the issues that we know are really important," Ely Ratner, assistant secretary of defense for Indo-Pacific security affairs, said last week at an event organized by the Hudson Institute in Washington.

The new framework under consideration is likely to involve working-level officials, with the United States planning to sort out the specifics of what is to be discussed in due course, according to the sources.

The U.S. proposal emerged after the South Korean government recently announced a plan to end a long-running dispute with Japan over wartime labor, raising hope for closer cooperation between Washington, Tokyo and Seoul, especially in the field of defense affairs.

In the Nuclear Posture Review, released in October last year, the administration of President Joe Biden also underscored the need to expand consultations on extended deterrence together with Japan and South Korea, and possibly Australia as well, as the security environment in the Indo-Pacific becomes increasingly severe.

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