The U.S. reaffirmed its "ironclad" security commitment for the key regional allies in a working-level video conference on the North's latest nuclear test, according to South Korea's defense ministry.
"In particular, the U.S. stressed that its extended deterrence commitment will be guaranteed through all categories of military capabilities including conventional and nuclear weapons," it said.
The three parties agreed to promote the trilateral interoperability of deterrence and response to the North's provocative acts.
They also agreed to keep cooperating in a campaign to apply "maximum pressure" on Pyongyang in order to force its leadership to abandon the nuclear and missile programs, said the ministry.
In the consultations, South Korea was represented by Choi Hyong-chan, director general of the ministry's international affairs. His American and Japanese counterparts were David Helvey, acting assistant secretary of defense for Asian and Pacific security affairs, and Satoshi Maeda, director general of the defense policy bureau.
Hours earlier, the South's Defense Minister Song Young-moo had phone talks with his American counterpart James Mattis. They agreed that it is important for the U.S. to deploy high-profile assets, such as bombers and aircraft carriers, more often to Korea, according to Song's office.
Some South Koreans even hope for the return of U.S. tactical nuclear weapons here or for their country's own nuclear development.
The government said there is no change in its denuclearization commitment, although various options may be considered to counter the growing threat from the North, source from the Yonhap.