Appearing with Japanese Foreign Minister Fumio Kishida at a news conference after their talks in Tokyo, Kerry, who was on the final leg of his Asia tour, also briefed his Japanese hosts on his earlier visits of South Korea and China. Kerry's Asian visit came amid North Korea's growing belligerence and dangerous threats that have sharply escalated tensions on the Korean Peninsula, even raising concerns about the North undertaking a ballistic missile test and about preemptive strikes.
Kerry said he informed Kishida "the goal of both China and the Republic of Korea is the denuclearization of North Korea." China is the North's closest ally and its chief supplier of aid.
The U.S. visitor said: "We are committed to take action together -- we, Japan, the United States. And the other countries that I have met with in the last two days are committed to make that goal of denuclearization a reality."
He assured the U.S.-Japan alliance "has really never been stronger than it is today, and the U.S. is fully committed to the defense of Japan," adding: "The biggest priority is a peaceful resolution to the issues of North Korea."
Kishida said "a lot of time" was devoted to discussion on North Korea in his talks with Kerry, while other issues also were discussed related to Asia Pacific.
"We agreed North Korea must immediately stop its provocative speech and behavior, and show it is taking specific towards denuclearization," the Japanese minister said. "We cannot in any way allow North Korea to possess nuclear weapons.
He said he and Kerry "agreed that it is important for [the] U.S., Japan and South Korea to deepen collaboration."
On the security front, Kishida said Japan welcomes the fact that the United States is maintaining a strategy of rebalancing toward the Asia Pacific, and is positioned to retain its defense commitment under the U.S.-Japan alliance.
"I believe the meeting was very substantive and fit to conclude the secretary's first visit to Asia," Kishida .
Answering questions, Kerry expressed hope that North Korea "will hear our words and recognize that the future of its people and for the future stability in the region as well as on the peninsula itself, there is a clear course of action that they are invited to take, and they will find in us ready partners to negotiate in good faith to resolve this issue."
On the offer from South Korea's president to engage in dialogue with North Korea, Kerry said it should be welcomed.
"I think she has shown great courage in her willingness to try to move in a different direction, providing she has a willing partner to move in that direction with," the secretary said.
"Obviously right now, that can't happen. But I think it's important that she has made clear that the policy of her government will be to build a trust-politic approach to this issue in the future, and I think everybody should welcome that."
Kishida, commenting on the North's warning that Japan would be the first target in the event of a war, said Japan is "making all out preparation for such contingencies."
To avoid such a situation, he said, Japan needs to strengthen its international collaboration.
"And therefore, [the] U.S., Japan, and other relevant countries need to further strengthen our relationship, and Japan is working towards this end," Kishida said. He also said the North must be made to "understand that such behavior will not benefit them in any way whatsoever."
Kerry said it is "really unfortunate that there has been so much focus and attention, both within the media and elsewhere, on the subject of war, when what we really ought to be talking about is the possibilities of peace."
He said the North must understand "that its threats and its provocations are only going to isolate it further and impoverish its people even further."
He said while President Obama has made it clear the United States will do what is necessary to defend it allies, "our choice is to negotiate."
"And we would hope that whatever considerations or fears the North has -- of the United States or of others in the region that they would come to the table in a responsible way and negotiate that.'
Kerry said the United States is confident it can address the North's concerns with respect to their security and "find ways together with China and the Republic of Korea and Japan and Russia and the members of the Six-Party Talks, we can find a way to resolve these differences at a negotiating table."
Kerry spent the early part of the day visiting a 620-year-old Buddhist temple and meeting with university students to hear their views on America and other global issues.
The United States asked any airplanes to report to the U.S. military if they fly near its Kadena base in Okinawa prefecture, Japan's Kyodo News reported. The request was made as part of precautions being taken against possible North Korean missile launches, CNN reported.